🗂️ refactor: Move Pane Composer Files to Jotai in the Chat Package

[berry-13]

Pull Request

Summary

The files staged in each chat pane's composer lived in a Recoil atom family (filesByIndex in client/src/store/families.ts), so useChatHelpers, useNewConvo, useNewChat, the files table and the sign-out reset all reached into ~/store for state that only the chat pane owns.

This moves that state to a Jotai family, filesFamily, under packages/chat/src/react/pane/ (exported from @librechat/chat/react) together with all six consumers. The ExtendedFile type the family holds moves to packages/chat/src/core/files.ts; ~/common re-exports it, so existing imports are unchanged. Behavior is the same: each pane starts with an empty map, and sign-out clears every pane except the kept first one.

Stacked on #17179, which moves the pane preset and option settings the same way; both edit the same consumers. This continues moving feature-owned chat state onto Jotai inside the chat package and cutting the chat hooks' reads of ~/store.

Type of change

• Refactor

Testing

Tested environments/configuration:

• No runtime configuration involved; the change swaps the state library with identical defaults and the same consumers.

Automated tests:

• pane.spec.ts now covers the files family's empty default and per-pane isolation.
• The useClearStates per-pane reset case now also asserts that staged files are cleared on sign-out.
• The ChatForm specs read files from the Jotai family and reset it after each test, since the default Jotai store outlives each test's RecoilRoot. The useNewChat and useNewConvo specs back their file maps with the real atom instead of a mocked Recoil hook.
• npx jest over Chat/Input (including the files table), hooks/Chat/__tests__, useClearStates, hooks/Conversations, useNewConvo and Chat/Menus: 91 suites, 1662 tests passed.
• npm run typecheck in client and packages/chat: no errors. ESLint, Prettier and import sorting clean on the changed files.

Screenshots / recordings

No user-facing change.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-16T21:07:25.984258Z	42e672f	New commits
🔒 Security Review	✅ Completed 2026-10-16T19:45:56.891767Z	810f98a	PR opened

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