release: add workflow_dispatch trigger for on-demand (draft) builds

[mariotaku]

Why

The release pipeline only triggered on release: published, so cutting a release required manually creating the GitHub Release in the UI first. There's no way to build the .deb artifacts on demand (e.g. to validate a release, or to produce a draft for review).

What

Add a workflow_dispatch trigger to release.yml:

• tag input (required) — the tag to create the release on, e.g. v20260626-cd038b0.
• draft input (default true) — create the release as a draft for review before publishing.

The ncipollo/release-action step now falls back to the dispatch inputs:

tag:   ${{ github.event.release.tag_name || inputs.tag }}
name:  Release ${{ github.event.release.tag_name || inputs.tag }}
draft: ${{ github.event_name == 'workflow_dispatch' && inputs.draft }}

The existing release: published behaviour is unchanged (for that event inputs.tag is empty and draft evaluates to false).

Use

Once merged, a release can be cut on demand (Actions → Release → Run workflow, or via API) — it builds all four toolbox debs and attaches them to a draft release at the given tag, ready to review and publish.

This is the mechanism to ship the global-scope symbol-resolution fix (#1) as v20260626-cd038b0.

🤖 Generated with Claude Code

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