[Feature Request] Add GUI menu option to restart Claude Desktop

Currently, restarting Claude Desktop on Windows requires right-clicking the system tray icon and selecting Quit, then relaunching manually. This is friction-heavy, especially when you need to pick up config changes or clear a stuck state.

Request: Add a restart option accessible from within the app itself, e.g.:

• A File → Restart menu item
• A right-click option in the app's own menu/header
• Or a keyboard shortcut

Related: #34320 requests a /restart chat command — this is complementary but distinct (GUI-level, not chat-level).