Create command palette and add new features for search and actions (#728)

* refactor(ui): replace in-repo Command primitive with cmdk wrapper

* feat(command-palette): add global Cmd+K palette with v1 actions

* feat(command-palette): add session, file, and commit search sources

* refactor: add provider names to model constants

* feat(command-palette): add settings, navigation, message search, and ⌘K hints

* feat(command-palette): add git fetch/pull/push and branch switch actions

* refactor(command-palette): consolidate fetch source hooks behind useApiSource

* refactor(command-palette): extract useCommandKey and SETTINGS_MAIN_TABS metadata

* refactor(command-palette): extract groups into declarative registry

* refactor(command-palette): wire openFile through PaletteOpsContext

* refactor: migrate openSettings and refreshProjects from window.* to PaletteOpsContext

* refactor(command-palette): inline groups and delete registry indirection

* refactor(command-palette): return items array directly from source hooks

* refactor(palette-ops): flatten Handle wrapper into ref-based registry

* refactor: inline useCommandKey as MOD_KEY constant in two call sites

* feat: introduce pages and fix bug on branch switching

* fix: small labels

* fix: coderabbit issues

* fix: coderabbit comments

* Update src/components/chat/view/subcomponents/ProviderSelectionEmptyState.tsx

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

---------

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

src/components/sidebar/view/subcomponents/SidebarHeader.tsx

@@ -5,6 +5,9 @@ import { IS_PLATFORM } from '../../../../constants/config';
 import { cn } from '../../../../lib/utils';
 import GitHubStarBadge from './GitHubStarBadge';
 
+const MOD_KEY =
+  typeof navigator !== 'undefined' && /Mac|iPhone|iPad/.test(navigator.platform) ? '⌘' : 'Ctrl';
+
 type SearchMode = 'projects' | 'conversations';
 
 type SidebarHeaderProps = {
@@ -148,9 +151,9 @@ export default function SidebarHeader({
                 placeholder={searchMode === 'conversations' ? t('search.conversationsPlaceholder') : t('projects.searchPlaceholder')}
                 value={searchFilter}
                 onChange={(event) => onSearchFilterChange(event.target.value)}
-                className="nav-search-input h-9 rounded-xl border-0 pl-9 pr-8 text-sm transition-all duration-200 placeholder:text-muted-foreground/40 focus-visible:ring-0 focus-visible:ring-offset-0"
+                className="nav-search-input h-9 rounded-xl border-0 pl-9 pr-14 text-sm transition-all duration-200 placeholder:text-muted-foreground/40 focus-visible:ring-0 focus-visible:ring-offset-0"
               />
-              {searchFilter && (
+              {searchFilter ? (
                 <button
                   onClick={onClearSearchFilter}
                   aria-label={t('tooltips.clearSearch')}
@@ -158,6 +161,15 @@ export default function SidebarHeader({
                 >
                   <X className="h-3 w-3 text-muted-foreground" />
                 </button>
+              ) : (
+                <kbd
+                  aria-hidden
+                  title={t('tooltips.openCommandPalette')}
+                  className="pointer-events-none absolute right-2.5 top-1/2 hidden -translate-y-1/2 items-center gap-0.5 rounded border border-border/60 bg-muted/40 px-1.5 py-0.5 font-mono text-[10px] text-muted-foreground md:inline-flex"
+                >
+                  {MOD_KEY}
+                  <span>K</span>
+                </kbd>
               )}
             </div>
           </div>