fix(plugin-types): ActionsAPI.register handler exec-context d.ts (fn-176.1)

[acebytes]

Summary

Fixes known d.ts drift F1: ActionsAPI.register declared its handler as (input: AnyJSONValue) => ..., but the host invokes handlers with a single exec-context object — { invocationId, source, input, sourceId? } (host truth: AppOS-Desktop PluginActionsBridge.swift:1332-1348; host's own plugin-api.d.ts already agrees).

Flow tracking: fn-176.1 (epic fn-176-sdk-fix-actionsapiregister-handler-dts, AppOS-Desktop .flow/).

Changes

• namespaces-core-plugins.ts — export InvocationSource ("user" | "plugin" | "agent" | "recipe" | "sequence" | "system") and ActionExecutionContext (invocationId: string; source: InvocationSource; input: AnyJSONValue; sourceId?: string, no index signature); register's handler param is now (exec: ActionExecutionContext); return type and def param unchanged; JSDoc describes exec-context dispatch. notifications.emit(input: AnyJSONValue) untouched (genuine input param).
• TS2304 doc guidance — src/index.ts header and README.md drop the /// <reference types="@appos.space/plugin-types" /> suggestion (package ships module exports only — no ambient globals); import-only guidance remains. README version mapping made version-agnostic (review r1).
• New compile-only typetest src/__tests__/actions.typetest.ts importing via the public entrypoint (../index): (a) ytdlp's (exec) => exec.input as SomeShape pattern with displayName/risk/tags def extras; (b) field reads; (c) @ts-expect-error undeclared prop; (d) @ts-expect-error incompatible handler param; (e) @ts-expect-error non-member source literal comparison.
• tsconfig.json — exclude docs-site from the root lint project (root npm run lint has been red since PR feat: automated developer docs site (TypeDoc + Starlight + CI) #4: Astro's astro:content virtual module + docs-site node_modules get swept; docs-site has its own toolchain/CI).
• package-lock.json — 1-line sync of the plugin-types workspace stanza to the pre-staged 3.0.0.

Empirical probe outcomes (recorded in the typetest, flagged to fn-176.3 release task)

• Case (f) dropped per task fallback rule: a legacy explicitly-typed (input: AnyJSONValue) handler does NOT assign (TS2345 — interfaces get no implicit index signature, so ActionExecutionContext is not assignable to AnyJSONValue's object arm). Changelog language for the release: source-breaking-but-runtime-correcting. Untyped (input) => ... handlers keep compiling at the call site.
• Interface assertion caveat: exec.input as SomeInterface fails TS2352 (same TS rule); a type-alias target compiles. Real-ytdlp evidence: full tsc --noEmit against this build yields exactly one error (TS2352 at register-actions.ts:216, its interface DownloadUrlInput) — the original F1 error ("Property 'input' does not exist") is gone. Counterfactual input: unknown (host-d.ts parity) compiles ytdlp clean; the spec's R1 chose AnyJSONValue — decision deferred to the release task / ytdlp workstream (1-line interface → type on their side also resolves it).

Evidence

• npm run build RC=0 · npm test RC=0 (typetest enforced — unused @ts-expect-error fails compile) · root npm run lint RC=0
• dist verification: dist/namespaces-core-plugins.d.ts contains ActionExecutionContext (re-exported via dist/index.d.ts export *; package-name import probe resolves RC=0); zero handler: (input: AnyJSONValue) in dist/
• Grep gates: zero /// <reference types="@appos.space/plugin-types" and zero stale handler shape repo-wide (node_modules excluded)
• Codex impl-review: round 1 NEEDS_WORK (1 Minor: README version mapping) → fixed → round 2 SHIP

Not in this PR

• No merge to main without review; no npm publish — release is fn-176.3 (user-gated ./release.sh, occupancy-guarded 3.0.0-vs-3.0.1 decision).
• Docs-site drift gate + full build verification is fn-176.2.