feat(cli): add direct argument support for /approval-mode command

[tt-a1i]

Summary

This PR adds the ability to set approval mode directly via command argument, without needing to open the interactive dialog.

New Usage:

/approval-mode plan       # Set to plan mode directly
/approval-mode yolo       # Set to yolo mode directly  
/approval-mode auto-edit  # Set to auto-edit mode directly
/approval-mode default    # Set to default mode directly

Behavior:

• If no argument is provided, opens the dialog as before (backward compatible)
• If a valid mode is provided, sets the mode directly and shows confirmation
• If an invalid mode is provided, shows error with list of valid modes
• Tab completion is supported for mode arguments

Note: Direct argument mode always saves to User scope. The interactive dialog still allows choosing between User/Workspace scopes.

Changes

• Modified approvalModeCommand.ts to parse and handle direct mode arguments
• Added completion function for tab completion support
• Updated tests to cover new functionality (including explicit setApprovalMode argument assertions)
• Added i18n translations (en, zh, ru)

Fixes #1353

AI Assistance Disclosure

I used Codex to review the changes, sanity-check the implementation against existing patterns, and help spot potential edge cases.

[tanzhenxin]

@tt-a1i Thanks for your contribution! I’m not sure it’s a good idea to set approval mode at the user scope, since it could easily be overridden by the project scope setting. You can try this out using the /approval-mode dialog.

From my perspective, this issue is more of a power-user requirement rather than a typical CLI use case. So I’m thinking we could keep things simple: no autocomplete, and when a user runs /approval-mode xxx, we apply it only at the session scope—without persisting it to either the project or user scope. This would be similar to how the Shift+Tab shortcut works.

What do you think about this approach?

[tt-a1i]

@tt-a1i Thanks for your contribution! I’m not sure it’s a good idea to set approval mode at the user scope, since it could easily be overridden by the project scope setting. You can try this out using the /approval-mode dialog.

From my perspective, this issue is more of a power-user requirement rather than a typical CLI use case. So I’m thinking we could keep things simple: no autocomplete, and when a user runs /approval-mode xxx, we apply it only at the session scope—without persisting it to either the project or user scope. This would be similar to how the Shift+Tab shortcut works.

What do you think about this approach?

thanks for the feedback! updated:

• removed persistence, now session-only (just config.setApprovalMode())
• dropped autocomplete

also added try/catch for the untrusted folder case since setApprovalMode can throw there.

[tanzhenxin]

LGTM!