[faster-connectors] (1/4) Extract apps cache logic into ConnectorRuntimeManager

[mzeng-openai]

What

• Extract the existing Codex Apps tools cache behind ConnectorRuntimeManager, ConnectorRuntimeContext, and an immutable tools-plus-refresh-time snapshot.
• Scope the active runtime context by account, ChatGPT user, workspace-account mode, and Codex home; discard stale contexts on context changes.
• Keep the existing schema-v4 tools-only cache wire format, while adding a 32 MiB bounded read, file-mtime cold-load bookkeeping, and atomic replacement.
• Retain compatibility aliases so existing app/list callers and startup behavior do not change in this slice.
• Prevent discarded contexts from advertising or executing their old Apps tools, and serialize accepted snapshot persistence so disk cannot regress behind memory.

Why

This is stack PR 1 of 4 for the connector runtime state refactor. It establishes one owner for committed connector runtime state before later PRs add explicit refresh serialization, request-stable consumption, and the v2 app/installed API.

The snapshot intentionally contains runtime facts only: the raw /ps/mcp tools/list ToolInfo set and refreshed_at. Connector directory metadata remains owned by app/read / ConnectorMetadataStore.

Compatibility and impact

• No public app-server API change.
• No app/list behavior change.
• No _meta.installedApps dependency.
• No connector-directory fetch during runtime load or publication.
• The persisted schema remains { "schema_version": 4, "tools": [...] }, so existing caches remain readable.

Checks

• just test -p codex-mcp (112 passed)
• just fmt

[chatgpt-codex-connector]

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[mzeng-openai]

@codex review

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 95f76cd3e0

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".