feat(desktop-client): give login and main views their own BrowserWindow

Spawn a separate window per mode keyed by a ?window= query param so each surface keeps its size, devtools, and renderer state independently. Logout now persists the cleared session and switches windows before awaiting the runtime release, avoiding a stale main-window flash on the way out.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/desktop-client/src/renderer/App.vue

@@ -1,14 +1,23 @@
 <script setup lang="ts">
-import { defineAsyncComponent, onMounted, watch } from "vue";
+import { computed, defineAsyncComponent, onMounted, watch } from "vue";
 import { useDesktopSession } from "./composables/useDesktopSession";
 
 const DesktopShell = defineAsyncComponent(() => import("./components/DesktopShell.vue"));
 const LoginView = defineAsyncComponent(() => import("./views/LoginView.vue"));
 
 const { isAuthenticated, syncRuntimeSession } = useDesktopSession();
+type RendererWindowMode = "auto" | "login" | "main";
 
 interface WindowModeBridge {
-  setWindowMode?: (mode: "login" | "main") => Promise<unknown>;
+  setWindowMode?: (
+    mode: "login" | "main",
+    request?: { source?: "auth-state" | "login" | "logout"; animate?: boolean },
+  ) => Promise<unknown>;
+}
+
+function resolveRendererWindowMode(): RendererWindowMode {
+  const mode = new URLSearchParams(window.location.search).get("window");
+  return mode === "login" || mode === "main" ? mode : "auto";
 }
 
 function getModeBridge(): WindowModeBridge | undefined {
@@ -18,21 +27,42 @@ function getModeBridge(): WindowModeBridge | undefined {
 }
 
 function syncWindowMode(authenticated: boolean): void {
-  void getModeBridge()?.setWindowMode?.(authenticated ? "main" : "login");
+  void getModeBridge()?.setWindowMode?.(authenticated ? "main" : "login", { source: "auth-state" });
 }
 
-// Fire immediately during setup so the main process can size + reveal the
-// window before the user sees any "wrong-sized" frame.
-syncWindowMode(isAuthenticated.value);
-watch(isAuthenticated, (next) => syncWindowMode(next));
+const rendererWindowMode = resolveRendererWindowMode();
+const usesAutomaticWindowMode = rendererWindowMode === "auto";
+const showsMainSurface = computed(() =>
+  rendererWindowMode === "main" || (rendererWindowMode === "auto" && isAuthenticated.value),
+);
+
+if (usesAutomaticWindowMode) {
+  syncWindowMode(isAuthenticated.value);
+  watch(isAuthenticated, (next) => syncWindowMode(next));
+}
+
+if (rendererWindowMode === "main") {
+  if (!isAuthenticated.value) {
+    syncWindowMode(false);
+  }
+  watch(isAuthenticated, (next) => {
+    if (!next) {
+      syncWindowMode(false);
+    }
+  });
+}
 
 onMounted(() => {
-  void syncRuntimeSession();
-  syncWindowMode(isAuthenticated.value);
+  if (rendererWindowMode !== "login") {
+    void syncRuntimeSession();
+  }
+  if (usesAutomaticWindowMode) {
+    syncWindowMode(isAuthenticated.value);
+  }
 });
 </script>
 
 <template>
-  <DesktopShell v-if="isAuthenticated" />
+  <DesktopShell v-if="showsMainSurface" />
   <LoginView v-else />
 </template>