Adds a "Start in fullscreen" toggle to the Settings → System panel,
addressing the desktop request in feedBack-desktop#97: users want the
app to launch fullscreen without hitting the OS hotkey every time.
The block ships hidden and is gated exactly like the App-updates block:
setupWindowOptions() only unhides + wires it when the feedBack-desktop
bridge exposes window.feedBackDesktop.window.{getStartFullscreen,
setStartFullscreen}. Web/Docker builds have no such bridge, so the
section never appears there. Persistence lives desktop-side because
only the Electron main process can read the pref at window-creation
time — core just proxies through the bridge.
The desktop bridge + launch behaviour land in a follow-up
feedBack-desktop PR.
Signed-off-by: gionnibgud <gionnibgud@gmail.com>
f8012a8ce4