feat: add compact mode for minimal widget interface (#36)

Add a compact mode that shrinks the window to a small widget showing
just the character sprite, recent messages, and a quick input box.
Perfect for quick questions while working without the full UI.

- Add CompactMode.svelte component with minimal widget interface
- Add compact mode toggle in StatusBar (Ctrl+Shift+M shortcut)
- Save/restore window size when toggling compact mode
- Handle display scaling by converting physical to logical pixels
- Add compact_mode to config (Rust + TypeScript)
- Add required Tauri window permissions for resize operations

src/lib/components/KeyboardShortcutsModal.svelte

@@ -12,6 +12,8 @@
         { keys: ["Escape"], description: "Close modals and panels" },
         { keys: ["Ctrl", "L"], description: "Clear the terminal" },
         { keys: ["Ctrl", ","], description: "Open settings" },
+        { keys: ["Ctrl", "Shift", "M"], description: "Toggle compact mode" },
+        { keys: ["Ctrl", "Shift", "S"], description: "Toggle streamer mode" },
       ],
     },
     {