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>

ui/titlebar.js

@@ -0,0 +1,50 @@
+// The title bar. Moving and double-click maximising come from `data-tauri-drag-region`; the
+// buttons call the window directly; the menu and the agent pill open the app's native menu (the
+// tray's items), which can reach past this 36-pixel-high page.
+"use strict"
+
+const { invoke } = window.__TAURI__.core
+const { listen } = window.__TAURI__.event
+const win = window.__TAURI__.window.getCurrentWindow()
+
+const $ = (id) => document.getElementById(id)
+
+const WORDS = {
+  off: "agent off",
+  not_linked: "not linked",
+  starting: "agent starting…",
+  running: "agent running",
+  elsewhere: "agent running (service)",
+  failed: "agent stopped",
+}
+
+function render(s) {
+  let host = ""
+  try {
+    host = s.server ? new URL(s.server).host : ""
+  } catch {}
+  $("host").textContent = host
+  $("host").title = s.server || ""
+  const state = s.agent.state
+  $("agent").dataset.state = state
+  $("agent-text").textContent = WORDS[state] ?? state
+  $("agent").title = state === "failed" ? `Agent stopped: ${s.agent.detail}` : "Agent"
+}
+
+function maximized(on) {
+  const b = $("maximize")
+  b.toggleAttribute("data-maximized", on)
+  b.setAttribute("aria-label", on ? "Restore" : "Maximise")
+  b.title = on ? "Restore" : "Maximise"
+}
+
+$("minimize").addEventListener("click", () => win.minimize())
+$("maximize").addEventListener("click", () => win.toggleMaximize())
+$("close").addEventListener("click", () => win.close())
+$("menu").addEventListener("click", () => invoke("titlebar_menu"))
+$("agent").addEventListener("click", () => invoke("titlebar_menu"))
+
+listen("status", (e) => render(e.payload))
+listen("maximized", (e) => maximized(!!e.payload))
+invoke("get_status").then(render)
+win.isMaximized().then(maximized)