Create WraithApp struct in internal/app that initializes SQLite,
runs migrations, seeds themes, and exposes vault management methods
(IsFirstRun, CreateVault, Unlock, IsUnlocked) to the frontend.
Register WraithApp, ConnectionService, ThemeService, and SettingsService
as Wails v3 bound services.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
