LLeMbas's own window, the leaf icon, one name for the app

- The window has no system decoration: a local title bar webview (agent
  state, a native menu with the tray's items, window buttons) above the
  content webview, which stays remote with no IPC. Laid out on resize,
  with a frame to resize by unless maximized.
- Icons from the transparent pixel leaf, not the server's tiled icon.
- productName llembas-desktop: package, .desktop file and the window's
  app id now match (KWin showed a generic icon); the visible name stays
  LLeMbas through a desktop template. Replaces the 0.1.0 package l-le-mbas.
- The bundled CLI is a resource in the app's own directory, not
  /usr/bin/lembas.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src-tauri/capabilities/default.json

@@ -1,7 +1,15 @@
 {
   "$schema": "../gen/schemas/desktop-schema.json",
   "identifier": "default",
-  "description": "The app's own pages (the first-run page). The server's web UI is a remote page and gets no IPC at all: this capability lists no remote URLs.",
+  "description": "The app's own pages: the title bar and the first-run page. The server's web UI is a remote page in the same window and gets no IPC at all: this capability lists no remote URL. The window permissions are the title bar's: moving, resizing, minimising, maximising and closing (which hides).",
   "windows": ["main"],
-  "permissions": ["core:default"]
+  "permissions": [
+    "core:default",
+    "core:window:allow-start-dragging",
+    "core:window:allow-start-resize-dragging",
+    "core:window:allow-internal-toggle-maximize",
+    "core:window:allow-minimize",
+    "core:window:allow-toggle-maximize",
+    "core:window:allow-close"
+  ]
 }