feat: vault management — remove vault from list and restore Getting Started

Add ability to remove vaults from the app list without deleting files on disk,
and restore the bundled Getting Started demo vault when needed.

Changes:
- Rust: add hidden_defaults field to VaultList for tracking removed default vaults
- useVaultSwitcher: add removeVault() and restoreGettingStarted() with auto-switch
- useCommandRegistry: add 'Remove Vault from List' and 'Restore Getting Started Vault' commands
- StatusBar: add X button per vault item in vault menu dropdown
- 25 new tests covering removal, restore, edge cases, and command palette

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/hooks/useCommandRegistry.ts

@@ -55,6 +55,10 @@ interface CommandRegistryConfig {
   onSwitchTheme?: (themeId: string) => void
   onCreateTheme?: () => void
   onOpenTheme?: (themeId: string) => void
+  onRemoveActiveVault?: () => void
+  onRestoreGettingStarted?: () => void
+  isGettingStartedHidden?: boolean
+  vaultCount?: number
 }
 
 const PLURAL_OVERRIDES: Record<string, string> = {
@@ -187,6 +191,7 @@ export function useCommandRegistry(config: CommandRegistryConfig): CommandAction
     themes, activeThemeId, onSwitchTheme, onCreateTheme, onOpenTheme,
     onCheckForUpdates, isUpdating,
     onCreateType,
+    onRemoveActiveVault, onRestoreGettingStarted, isGettingStartedHidden, vaultCount,
   } = config
 
   const hasActiveNote = activeTabPath !== null
@@ -242,6 +247,8 @@ export function useCommandRegistry(config: CommandRegistryConfig): CommandAction
       // Settings
       { id: 'open-settings', label: 'Open Settings', group: 'Settings', shortcut: '⌘,', keywords: ['preferences', 'config'], enabled: true, execute: onOpenSettings },
       { id: 'open-vault', label: 'Open Vault…', group: 'Settings', keywords: ['vault', 'folder', 'switch', 'open', 'workspace'], enabled: true, execute: () => onOpenVault?.() },
+      { id: 'remove-vault', label: 'Remove Vault from List', group: 'Settings', keywords: ['vault', 'remove', 'disconnect', 'hide'], enabled: (vaultCount ?? 0) > 1 && !!onRemoveActiveVault, execute: () => onRemoveActiveVault?.() },
+      { id: 'restore-getting-started', label: 'Restore Getting Started Vault', group: 'Settings', keywords: ['vault', 'restore', 'demo', 'getting started', 'reset'], enabled: !!isGettingStartedHidden && !!onRestoreGettingStarted, execute: () => onRestoreGettingStarted?.() },
       { id: 'check-updates', label: 'Check for Updates', group: 'Settings', keywords: ['update', 'version', 'upgrade', 'release'], enabled: !isUpdating, execute: () => onCheckForUpdates?.() },
 
       // Type-aware: "New [Type]" and "List [Type]"
@@ -254,6 +261,7 @@ export function useCommandRegistry(config: CommandRegistryConfig): CommandAction
     onQuickOpen, onCreateNote, onCreateNoteOfType, onCreateType, onSave, onOpenSettings,
     onTrashNote, onRestoreNote, onArchiveNote, onUnarchiveNote,
     onCommitPush, onSetViewMode, onToggleInspector, onToggleDiff, onToggleRawEditor, onToggleAIChat, onOpenVault,
+    onRemoveActiveVault, onRestoreGettingStarted, isGettingStartedHidden, vaultCount,
     onCheckForUpdates, isUpdating,
     onZoomIn, onZoomOut, onZoomReset, zoomLevel,
     onSelect, onOpenDailyNote, onCloseTab,