Restart app-server per workspace without full app restart (for account switching)

Trace how each workspace starts and owns its persistent codex app-server process, then inspect the workspace sidebar actions for an appropriate entry point. The implementation should provide a per-workspace reconnect or restart action that uses the current ~/.codex account without restarting the whole app; verify that subsequent requests use the refreshed process.

Problem

When using multiple Codex accounts via a tool like Codex Switcher, switching accounts updates ~/.codex but does not affect already-running workspace sessions in CodexMonitor. Each workspace has a persistent codex app-server process started at launch with the original account. After switching accounts externally, all requests continue to use the old session and fail with usageLimitExceeded.

The only workaround currently is a full app restart (Cmd+Q and reopen).

Expected Behavior

A way to restart the app-server for a specific workspace from within CodexMonitor — either via:

• A right-click context menu on the workspace
• A button in workspace settings
• Automatic detection of account changes in ~/.codex

Debug Log Evidence

Both workspaces return the same rate limit error after account switch:

"codexErrorInfo": "usageLimitExceeded"
"willRetry": false

Even after switching accounts externally, new turn/start requests go to the same exhausted session.

Suggested Fix

Add a Reconnect or Restart app-server option per workspace in the sidebar context menu. This would kill the current app-server process and spawn a fresh one, picking up whatever account is active in ~/.codex at that moment.