feat: phase 5 distribution — tauri shell, pwa, desktop release artifacts

- apps/desktop: Tauri 2 thin shell; connect screen stores the deployment
  URL, webview renders the remote console, tray with Show/Change Server/
  Quit, close-to-tray, single-instance
- frontend: vite-plugin-pwa generates manifest + Workbox SW (shell
  precache, /api /auth /mailpit NetworkOnly), install banner on
  beforeinstallprompt, rasterized PWA icons
- release.yml: desktop bundle matrix (linux/macos/windows) attached to
  GitHub Releases
- workspace 0.5.0; Dockerfiles copy the desktop workspace manifest

Authored By: TDvorak <[email protected]>

apps/frontend/src/App.tsx

@@ -31,6 +31,7 @@ import {
   NetworkError,
   OnboardingModal,
   ProjectDashboard,
+  PwaInstallBanner,
   type PaletteCommand,
   type ViewType,
 } from "./components";
@@ -1500,6 +1501,7 @@ export default function App() {
         <Show when={platformMessage()}>
           <div class="message message-neutral mb-5">{platformMessage()}</div>
         </Show>
+        <PwaInstallBanner />
 
         <Show
           when={platform() || isDemo}

apps/frontend/src/components/PwaInstallBanner.tsx

@@ -0,0 +1,58 @@
+import { Show, createSignal, onCleanup, onMount } from "solid-js";
+
+// Chromium fires `beforeinstallprompt` once manifest + service worker pass
+// installability checks. Stash the event and let the banner trigger it —
+// the native mini-infobar is easy to miss.
+interface BeforeInstallPromptEvent extends Event {
+  prompt(): Promise<void>;
+  userChoice: Promise<{ outcome: "accepted" | "dismissed" }>;
+}
+
+const DISMISS_KEY = "primora_pwa_install_dismissed";
+
+export function PwaInstallBanner() {
+  const [deferred, setDeferred] = createSignal<BeforeInstallPromptEvent | null>(null);
+  const [dismissed, setDismissed] = createSignal(localStorage.getItem(DISMISS_KEY) === "1");
+
+  onMount(() => {
+    const handler = (event: Event) => {
+      event.preventDefault();
+      // SAFETY: the listener is only attached to "beforeinstallprompt", whose
+      // event always carries prompt()/userChoice.
+      setDeferred(event as BeforeInstallPromptEvent);
+    };
+    window.addEventListener("beforeinstallprompt", handler);
+    onCleanup(() => window.removeEventListener("beforeinstallprompt", handler));
+  });
+
+  const install = async () => {
+    const event = deferred();
+    if (!event) return;
+    await event.prompt();
+    if ((await event.userChoice).outcome === "accepted") setDeferred(null);
+  };
+
+  const dismiss = () => {
+    localStorage.setItem(DISMISS_KEY, "1");
+    setDismissed(true);
+  };
+
+  return (
+    <Show when={deferred() && !dismissed()}>
+      <div
+        class="message message-info mb-5"
+        style="display:flex;align-items:center;justify-content:space-between;gap:1rem"
+      >
+        <span>Install Primora as an app for quick access from your launcher.</span>
+        <span style="display:flex;gap:0.5rem;flex-shrink:0">
+          <button class="btn btn-primary btn-sm" onClick={install}>
+            Install
+          </button>
+          <button class="btn btn-ghost btn-sm" onClick={dismiss}>
+            Not now
+          </button>
+        </span>
+      </div>
+    </Show>
+  );
+}

apps/frontend/src/components/index.ts

@@ -13,6 +13,7 @@ export { Modal, ModalFooter } from "./Modal";
 export { NotificationCenter, addNotification, removeNotification, clearNotifications, notify } from "./NotificationCenter";
 export { OnboardingModal } from "./OnboardingModal";
 export { Progress, CircularProgress, Spinner } from "./Progress";
+export { PwaInstallBanner } from "./PwaInstallBanner";
 export { ProjectDashboard } from "./ProjectDashboard";
 export { Table, DataTable, Pagination } from "./Table";
 export { Tabs, TabPanel } from "./Tabs";