/cwd command to switch working directory without restarting session

What variant of Codex are you using?

CLI (TUI) custom fork off of 0.104.0

What feature would you like to see?

Add a /cwd slash command to change the working directory inside the current TUI session, with a policy-selection step in the same flow.

Current workflow is frustrating:

1. Exit TUI
2. cd into another repo/worktree
3. codex resume ...
4. Re-approve sandbox/policy for that directory

This is especially painful when iterating on many sibling forks. I want Codex to keep autonomous execution within the selected repo, but I do not want to grant blanket access to the parent directory just to avoid repeated approvals.

Proposed UX:

• /cwd <path> to switch current working directory
• /cwd with no args opens a picker/input modal
• In the same flow, prompt for policy handling for the target directory:
• apply target directory defaults (trust/project policy)
• or keep current runtime policy override
• Show a short confirmation line in transcript (new cwd + effective approval/sandbox policy)

Additional information

Related but not equivalent: /add-dir (#11747) expands access roots; it does not switch active cwd and policy context.

Short implementation sketch:

1. Wire command + dispatch

• codex-rs/tui/src/slash_command.rs: add SlashCommand::Cwd with description and inline args support.
• codex-rs/tui/src/chatwidget.rs: dispatch /cwd and /cwd <path> via a new app event.

1. Add app-level event and handler

• codex-rs/tui/src/app_event.rs: add AppEvent::ChangeCwd { path: Option<String> }.
• codex-rs/tui/src/app.rs: handle ChangeCwd by resolving/validating path, then rebuilding config with existing rebuild_config_for_cwd(...).

1. Apply cwd + policy atomically

• Reuse rebuilt config’s derived approval/sandbox defaults for target cwd.
• Send Op::OverrideTurnContext { cwd: Some(...), approval_policy: Some(...), sandbox_policy: Some(...) } so core session state updates without restart.
• Update in-memory TUI state (self.config, file-search root via file_search.update_search_dir(...), and chat widget config copy) so UI and behavior stay consistent.

1. Prompt UI and tests

• Reuse/extend codex-rs/tui/src/cwd_prompt.rs patterns for selection/confirmation.
• Add tests in codex-rs/tui/src/chatwidget/tests.rs and codex-rs/tui/src/app.rs for command dispatch, path validation, and policy-application behavior.