release-please: track all multi-runtime manifests for every local plugin (drift cleanup)

[amondnet]

Follow-up from review on #240.

Context

The multi-format generator now emits four runtime manifests per local plugin (Claude Code, Codex, Antigravity, Cursor). However release-please-config.json only lists extra-files for 26 of ~70 local plugins — and even those only after #240 added .cursor-plugin/plugin.json at parity with the existing .codex-plugin/plugin.json entries.

The remaining ~44 plugins (e.g. plugins/nuxt, plugins/pinia) track only .claude-plugin/plugin.json, so on the next automated version bump their committed Codex/Antigravity/Cursor manifests will desync from the released version. (Raised by CodeRabbit on #240; the cursor-only partial fix was intentionally deferred here to avoid creating a new asymmetry.)

Scope

1. For every local plugin (source: "./plugins/..."), ensure its release-please-config.json entry's extra-files covers all generated version-bearing manifests it ships:
   • .claude-plugin/plugin.json
   • .codex-plugin/plugin.json
   • root plugin.json (Antigravity)
   • .cursor-plugin/plugin.json
2. Run bun scripts/cli.ts multi-format and commit the resulting Codex/Antigravity manifest regeneration (the pre-existing version drift that feat: add Cursor runtime support (multi-format manifests + scaffold skill) #240 deliberately left out of scope, e.g. 1.0.0 → current). This brings every generated manifest in sync with its Claude source.
3. Consider a CI check that fails when multi-format output is dirty, to prevent future drift.

Notes

• feat: add Cursor runtime support (multi-format manifests + scaffold skill) #240 kept its diff atomic (Cursor support only) by reverting ~149 files of unrelated Codex/Antigravity drift; this issue is the intended home for that cleanup.