feat: ship SDK 0.12 settings, structured commands and localization

[hkimw]

Adds SDK 0.12 configuration and display contracts so a user-operated host can validate scoped settings and structured commands, supply narrowly scoped secret references, and render localized metadata.

• Versioned memory settings use default/user/workspace precedence, CAS, subscriptions and explicit atomic migration. Secret leases bind plugin/workspace/command/execution, expiry and current authorization, with redacted errors and owned-byte cleanup.
• Normal commands and jobs validate input defaults and output schemas. Legacy parameters remain supported; new schema/display fields require a 0.12-aware peer. Cancelled normal operations retain their pending slot until their provider actually settles.
• Locale catalogs validate fallbacks, placeholders and display keys. Public helpers expose Intl formatting, accessibility names, shortcut conflicts and bounded theme contrast hints. Independent HTTP and browser examples cover settings, secrets and localization.
• Update declarations, 78 generated schemas, the explicit 343-file public package inventory, current packaging guidance and the 0.12 peer range while preserving prior published metadata verification.

Validation: 436 runtime tests; TypeScript positive/negative consumers; generated-schema drift and staged public-surface checks; installed archive consumer with the independent configuration HTTP example. Browser checks cover EN/KO, Arabic RTL with English fallback direction, long labels at a 390px viewport, light/dark appearance, keyboard execution, language changes during an operation, field errors, scoped reset and secret revocation. No console errors were observed. CI checks Windows/Linux on Node 22/24 before merge.

These are public SDK and independent example features. The settings store is in memory, trusted in-process callbacks are not sandboxed, and color/shortcut checks do not certify complete UI accessibility. DDS product UI/Engine/Cloud releases are outside this change.

DX: DDS-161, DDS-162, DDS-163.