## Why
Agent Plugins use a schema-declared root `plugin.json` and can have dotted names or versions that do not fit Codex's directory-safe version format. The packaging and installation paths still assumed the legacy manifest layout and identifier rules.
## What changed
- Recognize valid root Agent Plugin manifests when discovering, packing, and installing plugins, while leaving unrelated root manifests on the legacy path.
- Accept safe dotted plugin names, default missing Agent Plugin versions to `1.0.0`, and derive stable directory-safe versions when necessary without rewriting the portable manifest.
- Skip legacy command migration for Agent Plugins and reject symlinks or other unsupported file types while copying plugin sources.
## Testing
Add coverage for portable bundle round trips, manifest discovery, dotted names, version handling, command preservation, and symlink rejection.
GitOrigin-RevId: 61476c4c4100495842253d8b429c0b896490962d
## What changed
- Carry a plugin's local and remote identities together from plugin loading into
`SkillMetadata`.
- Resolve remote IDs from the installed-plugin snapshot when available, falling
back to persisted install metadata only when no snapshot exists.
- Include plugin identity in skill cache keys so identity changes refresh cached
skill metadata.
## Testing
- Cover snapshot and persisted identity resolution, local marketplace isolation,
cached skill refreshes, and propagation through plugin skill snapshots.
GitOrigin-RevId: aabeeb631a43361fe817358ace7f1ea8ba5db708
## Summary
- extract plugin identifiers and load-outcome types into codex-plugin
- update codex-core to consume the new plugin crate
## Testing
- CI
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Co-authored-by: Codex <noreply@openai.com>
