feat: keyboard mapping

[VictorlBueno]

Keyboard Shortcuts & Keymap Panel

This PR adds a keyboard shortcut system with a visual keymap panel, allowing users to view and remap all available shortcuts.

Keymap Panel (cmd-,)

• New modal panel listing all keyboard shortcuts grouped by category (Editor, Navigation, Panels, etc.)
• Live search to filter shortcuts by label or key binding
• Click any row to record a new key binding for that action
• Scrollable list with visible scrollbar
• Remappings are persisted and applied immediately via CustomKeymap

New Panel Shortcuts

Shortcut	Action
cmd-b	Toggle left panel
cmd-shift-b	Toggle right panel
cmd-shift-t	Toggle terminal
cmd-shift-r	Toggle query results
cmd-,	Toggle keyboard shortcuts

Smart Toggle Behavior (all panel shortcuts)

All shortcuts follow the same three-state logic:

• Panel closed → opens and immediately focuses it (keyboard navigation works right away)
• Panel open, not focused → focuses the panel without closing it
• Panel open and focused → closes it and returns focus to the editor

Tooltip Improvements

Dock buttons (terminal, results, left/right panel toggles) now show the bound keyboard shortcut in their tooltip via tooltip_with_action.

Bug Fixes

• Fixed cx.clear_key_bindings() wiping gpui-component Input bindings (backspace, cmd-a/c/v/x, undo, etc.) — re-registers them after each keymap reload
• Fixed keymap modal button remaining disabled after closing — resolved by synchronously focusing the workspace root on close before deferring editor focus
• Fixed shortcuts becoming unresponsive after closing a panel — all close paths now restore focus to the workspace root immediately, so shortcuts fire again without requiring a manual click

[fhsgoncalves]

Nice! 🌟