Add desktop visual feedback through **View → Toggle Annotations** / **Cmd+Shift+A**. Agentation starts hidden, opens directly in feedback mode, and leaves no floating launcher when closed. Saved notes survive toggles and window reopening; Copy produces structured feedback for a channel's composer. The toolbar follows open dialogs so their controls remain accessible while annotating Settings.

Pin Agentation 3.1.2 and include its license in the app assets. This release has no controlled-open API, so the small adapter uses its accessible launcher and scoped shadow styles; recheck these selectors when upgrading. Agentation is loaded only by the desktop UI.

Closes #208.

Validation: - `bun types`, `bun run ci`, production app build, and signed local desktop build. - React Doctor: 90/100; only the existing main App complexity warning. - Real native WebKit: no launcher on startup or close, keyboard and View menu toggles, save a note, copy/paste its structured output, preserve notes across window close/reopen, and save a second note inside Settings. The unsupported Hide Until Restart setting stays hidden so the shortcut remains available.

### Built in Ace

Dependency installation, checks, builds, React Doctor, and GitHub work ran through the `agentation-shortcut` channel's real Ace terminal. Implementation and review used Codex; Ace cannot yet host or resume this external harness (#9). Native smoke interaction and accessibility/screenshots used Codex's computer-use tools because this external harness cannot use Ace's channel-native tools directly (#9, #73).