feat: vite/ESM build, zero-hook initializer, public api.js module

[damyanpetev]

Fixes #233. Addresses the bootstrap audit in #256.

NOTE: ℹ️ Committed in separate chunks for review

Why

• The app.bundle.js → app.bootstrap.js → app.<hash>.bundle.js chain located its chunks by regexing its own script URL. Under .NET 9+ fingerprinting (@Assets[...]) that silently no-ops and the app renders blank (Ignite UI for Blazor stops working with .NET 9 Assets helper (no error but components not registered) #233).
• The script tag itself has been redundant since the JS initializer gained the Blazor Web App hooks: the bundle already auto-loads on every hosting model.
• igRegisterScript was a window global with no defined safe-point, and a script resolving before registration was dropped silently.

What changed

Build: webpack → vite, native ESM output.

• Chunks are ES modules resolved relative to their importer, so no runtime filename inspection exists anymore — the structural fix for Ignite UI for Blazor stops working with .NET 9 Assets helper (no error but components not registered) #233.
• Chunk shape matches the webpack output: one igniteui-core chunk (runtime plus all component metadata), our interop code as app, igniteui-webcomponents as the single lazy chunk. A commented knob in vite.config.mts splits the metadata into lazy per-component chunks instead.
• lit-html ships as a fixed-name module with its real exports (_content/IgniteUI.Blazor/lit-html.js), and every lit-html import in the graph goes through it, so an app mixing lit-based libraries can dedupe to one copy with a single import-map entry.
• Third-party license comments stay inline in the chunks, and vite's build.license emits THIRD-PARTY-LICENSES.md alongside the static assets.
• tsc --noEmit joins the build as the type-check gate (vite only transpiles), with types: [] so Node-only globals are compile errors. That surfaced one real bug: the in-process (WASM) data path referenced Node's global, which webpack had polyfilled; it is globalThis now.
• npm run build produces the complete wwwroot, themes included; the separate copythemes script and CI step are gone. webpack.config.js, the webpack dependencies, public_path.ts and the undocumented igPublicPath / InfragisticsBlazor globals are removed.

Loading: the JS initializer is the sole loader.

• IgniteUI.Blazor.Lite.lib.module.js is generated as a flat list of static imports covering the app entry's closure and api.js. It exports no hooks: Blazor awaits the module import, the module system awaits the imports. The graph loads in one hop instead of three.
• A missing bundle fails Blazor startup loudly with the failing URL, by design.
• app.bootstrap.js is deleted. app.bundle.js remains as a static shim for existing tags: it loads nothing and queues igRegisterScript / igRemoveScript calls made while the page parses, which api.js replays when it loads.

Public ES module _content/IgniteUI.Blazor/api.js (typings in api.d.ts):

• registerScript(name, fn, shouldCall = false) / removeScript(name). The default flips from the global's true: every *Script parameter in Lite except the value-supplying DataScript / ItemsScript wants the function itself, and every example (ours and the public grid docs) passed false explicitly. The deprecated global keeps true.
• html, lit-html's template tag, the same instance the components render with.
• The window globals keep working but warn once per API with the module import to use instead.
• A *Script name that is not registered when the component resolves it now logs a warning naming the script.

Docs and tests.

• Setup guidance drops the script tag for this package; the @Assets warning is scoped to the full product, whose loader still breaks under fingerprinting. *Script registration moves out of setup into its own components-skill reference (client-scripts.md). All *Script examples, including the 137 XML doc comments, use the module import, and every in-repo host follows the no-tag path.
• npm test (node --test, run in CI after the asset build) pins the built wwwroot invariants: no URL inspection, a plain-import initializer, real exports on api.js and lit-html.js, no internals in api.d.ts, legal notices present, the two shouldCall defaults, and the legacy stub's queue behaviour via node:vm.

Compatibility

• No C# or wire-format changes; the interop contract suite passes unchanged.
• Existing apps need no changes: the tag keeps working, including wrapped in @Assets[...], and the deprecated globals keep working with a console notice.
• Registering a *Script after its component rendered remains unsupported (now warns); order-independent registration is a separate follow-up.
• Re-hosting the assets (CDN/self-host), the one job igPublicPath could have done, is a standard import map prefix entry such as {"imports": {"./_content/IgniteUI.Blazor/": "https://cdn.example.com/ig/"}}, which relocates the whole graph, initializer included.

Verification

• Auto-load confirmed on Blazor Server, standalone WASM (trimmed publish, fingerprinted initializer in the boot config), Blazor Web App (all render modes), and BlazorWebView (.NET 10 WinForms runtime probe).
• Legacy path smoke: stub queue replay, parse-time-captured igTemplating.html at render time, one deprecation warning per API.
• Blazor Web App host: tag / no-tag / @Assets-tag matrix and module-registration cases confirmed.
• Full .NET test suite and npm test green.

🤖 Generated with Claude Code

[Copilot]

🟡 Changes recommended

The updated docs/samples use absolute /_content/... module specifiers that don’t align with the import-map prefix strategy described in the PR and should be made consistent.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

This PR modernizes the IgniteUI.Blazor.Lite static-web-assets pipeline and runtime initialization by switching the JS build to Vite + native ESM, adding a public _content/IgniteUI.Blazor/api.js module for *Script registration + lit-html templating, and removing the legacy bootstrap chain that breaks under .NET static-asset fingerprinting.

Changes:

• Replace webpack bootstrap flow with a Vite build that emits native ESM chunks plus a flat-import Blazor initializer module.
• Introduce public api.js + api.d.ts exports (registerScript/removeScript/html) and route legacy window globals through deprecated shims + a queueing app.bundle.js stub.
• Update docs/tests/templates/hosts to remove the redundant <script src="_content/IgniteUI.Blazor/app.bundle.js"> tag for Lite and to validate output invariants via node --test.

File summaries

File	Description
webpack.config.js	Removes the webpack-based bootstrap/build pipeline.
vite.config.mts	Adds Vite/Rolldown configuration to emit ESM bundles, fixed-name public modules, and a flat-import initializer.
tsconfig.json	Updates TS target/module resolution for bundler-style ESM output and tighter browser-only typing.
tsconfig.api.json	Adds a dedicated config to emit api.d.ts next to built api.js.
tests/js/static-web-assets.test.mjs	Adds node-based tests to pin wwwroot output invariants and legacy stub behavior.
tests/IgniteUI.Blazor.Lite.TestBed/wwwroot/app.js	Updates testbed script registration sample to use the public module API.
tests/IgniteUI.Blazor.Lite.TestBed/Components/App.razor	Removes redundant app.bundle.js tag from the Lite testbed host.
tests/IgniteUI.Blazor.Lite.PublishSmoke/wwwroot/index.html	Removes redundant app.bundle.js tag from the publish smoke host.
templates/README.md	Updates template guidance to no longer require the Lite script tag.
templates/IgniteUI.Blazor.Templates/templates/project/igb-blazor/IgniteBlazorApp.1/Components/App.razor	Removes redundant app.bundle.js tag from the template host.
stories/wwwroot/js/Chat.stories.js	Migrates story template registration from window globals to api.js imports.
stories/wwwroot/index.html	Removes redundant app.bundle.js tag from stories host page.
stories/Components/Stories/Welcome.md	Updates getting-started doc to remove script tag requirement.
stories/Components/Pages/IFramePage.razor	Removes redundant app.bundle.js tag and aligns guidance formatting.
src/src/public_path.ts	Removes webpack public-path global logic.
src/src/index.ts	Moves script registry lookup to api.ts, removes window globals, and fixes global → globalThis.
src/src/app.bundle.ts	Adds legacy classic-script stub that queues deprecated global calls until api.js loads.
src/src/api.ts	Adds the public API module (registerScript/removeScript/html) plus deprecated global shims + queue replay.
src/IgniteUI.Blazor.Lite.csproj	Updates the (commented) prebuild sample to run npm run build only.
src/components/Blazor/Accordion.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Banner.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/ButtonBase.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/ButtonGroup.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Calendar.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Carousel.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Chat.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/ChatRenderers.cs	Updates template XML docs to reference api.js registerScript + html usage.
src/components/Blazor/CheckboxBase.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Chip.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Combo.cs	Updates template + handler XML docs to reference api.js registerScript + html usage.
src/components/Blazor/DatePicker.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/DateRangePicker.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/DateTimeInput.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Dialog.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Dropdown.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/ExpansionPanel.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Input.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/InputBase.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/MaskInput.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/NavDrawer.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Radio.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/RadioGroup.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/RangeSlider.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Rating.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Select.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Slider.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Snackbar.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Splitter.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Stepper.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Tabs.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Textarea.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Tile.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/TileManager.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Tooltip.cs	Updates *Script XML docs to reference api.js registerScript usage.
src/components/Blazor/Tree.cs	Updates *Script XML docs to reference api.js registerScript usage.
skills/README.md	Expands skills index to note client-side *Script coverage.
skills/igniteui-blazor-theming/SKILL.md	Removes script-tag guidance from theming skill.
skills/igniteui-blazor-theming/references/common-patterns.md	Removes script-tag guidance from theming reference.
skills/igniteui-blazor-grids/SKILL.md	Updates grid skill guidance (Lite vs full product script-tag requirements).
skills/igniteui-blazor-grids/references/types.md	Updates FormatterScript guidance to reference registerScript.
skills/igniteui-blazor-grids/references/features.md	Updates export scripting example to use api.js.
skills/igniteui-blazor-generate-from-image-design/SKILL.md	Removes Lite script-tag requirement from image-design workflow.
skills/igniteui-blazor-components/SKILL.md	Updates setup guidance: Lite self-loads; adds *Script guidance and links.
skills/igniteui-blazor-components/references/setup.md	Clarifies theme-only requirement for Lite, and full-product caveats in Web Apps.
skills/igniteui-blazor-components/references/client-scripts.md	Adds new reference doc for registering *Script handlers/templates via api.js.
skills/AGENTS.md	Updates agent setup guidance to reflect Lite self-loading + full-product caveats.
README.md	Updates repo README: removes Lite script-tag setup and updates local build instructions.
package.json	Replaces webpack scripts with tsc --noEmit + vite build, adds node --test asset checks.
Directory.Build.targets	Updates comment to explain empty sentinel and non-MSBuild JS asset build.
CHANGELOG.md	Documents new public API, ESM build, deprecations, and fingerprinting fix.
.github/workflows/igniteui-blazor-lite-release.yml	Updates release workflow to run the new build (no separate theme copy).
.github/workflows/ci.yml	Updates CI to run new build and adds npm test asset verification.
.env.development	Adds a dev env file for NODE_ENV.

Review details

Suppressed comments (1)

skills/igniteui-blazor-components/references/client-scripts.md:33

• Same import-map concern as above: the classic-script example uses an absolute specifier ('/_content/…'), so an import-map prefix for "./_content/IgniteUI.Blazor/" would not apply. Using document.baseURI keeps it path-base-safe and aligns the specifier with the recommended prefix style.

- Other exports: `removeScript(name)`, and `html` — the lit-html template tag, the same instance the components render with. Typings ship at `_content/IgniteUI.Blazor/api.d.ts`.
- From a classic (non-module) script use a dynamic import: `const { registerScript, html } = await import('/_content/IgniteUI.Blazor/api.js');`
- The `igRegisterScript` / `igRemoveScript` / `igTemplating.html` window globals still work with the same signatures, but are deprecated and warn in the console.

• Files reviewed: 72/74 changed files
• Comments generated: 3
• Review effort level: Lite

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[Copilot]

🔵 Needs a closer look

Large cross-cutting changes to the JS build/bootstrapping and public JS API warrant human validation across hosting models and compatibility paths.

Review details

• Files reviewed: 72/74 changed files
• Comments generated: 3
• Review effort level: Lite

[Copilot]

🟡 Changes recommended

Legacy queue replay changes call ordering, while the public API and development type-checking also need correction.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Review details

Suppressed comments (1)

Previously missed (1) — in code that hasn't changed since the last review.

src/src/api.ts:40

• This registry accessor is emitted in api.d.ts and therefore becomes part of the supported public module surface, although the changelog and client-script documentation expose only registerScript, removeScript, and html. Keep lookup internal (for example via a shared internal registry module), or explicitly document and commit to this API before release.

• Files reviewed: 72/74 changed files
• Comments generated: 2
• Review effort level: Balanced

[Copilot]

🟡 Changes recommended

Public typings expose an internal registry type, and the new script guidance includes unsupported full-product and parse-time-global scenarios.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Review details

Suppressed comments (1)

skills/igniteui-blazor-components/references/client-scripts.md:34

• Without the legacy app.bundle.js tag, api.js is not imported until Blazor starts, so a classic script that calls these globals during page parsing sees igRegisterScript as undefined. Qualify the compatibility statement so users removing the now-optional tag do not break existing parse-time registrations.

- The `igRegisterScript` / `igRemoveScript` / `igTemplating.html` window globals still work with the same signatures, but are deprecated and warn in the console.

• Files reviewed: 72/74 changed files
• Comments generated: 4
• Review effort level: Balanced

[Copilot]

🟡 Changes recommended

The client-script documentation incorrectly promises order-independent module execution, which can race Blazor startup and permanently miss registrations.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Review details

• Files reviewed: 71/73 changed files
• Comments generated: 1
• Review effort level: Balanced

[Copilot]

🟡 Changes recommended

The Vite dependency requires Node 22.12+, conflicting with the documented Node 22+ prerequisite.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Review details

• Files reviewed: 71/73 changed files
• Comments generated: 1
• Review effort level: Balanced

[kdinev]

Explain why the licensed package needs it. Just a short reason.

[kdinev]

This place also needs a short answer to "Why?".

[kdinev]

This differs from the explanation in our dotnet/skills skill: https://github.com/dotnet/skills/pull/1111/changes#diff-6fbe289f6bfc3d6caa7652f7b348ca92b9af9e27c0dd5b3f6ce96cc49794a22bR44

In this one:

1. List the modules in the licensed package that components don't function without.
2. For the rest, explain that the modules are for eager loading, but if not includes would be lazy-loaded.

[kdinev]

Is this applicable when not using a grid or chart component, since we haven't yet ripped the rest of the components out of IgniteUI.Blazor and haven't made IgniteUI.Blazor.Lite a dependency yet?

[kdinev]

So, if I get this correctly, we will drop this requirement in 26.2?

[kdinev]

This statement The theme stylesheet is the only required tag goes in conflict with the next statement that IgniteUI.Blazor also requires a script tag with the app.bundle.js referenced.

[kdinev]

Why should I register its module explicitly?

[kdinev]

This commit all looks good.

I approved only the changes in a single commit

[kdinev]

I've submitted multiple review comments. Please take a look.