feat: strengthen module contracts and shared WebUI runtime

webui/src/layout/Titlebar.tsx

@@ -6,18 +6,13 @@ import LanguageMenu from "./LanguageMenu";
 import LoginModal from "../features/auth/LoginModal";
 import DismissibleAlert from "../components/DismissibleAlert";
 import { useGuardedNavigate, useUnsavedChanges } from "../components/UnsavedChangesGuard";
-import { apiFetch, isApiError } from "../api/client";
+import { useSharedNotificationSummary } from "../api/notificationSummary";
 import { logout, switchTenant } from "../api/auth";
 import { hasAnyScope } from "../utils/permissions";
 import { usePlatformLanguage } from "../i18n/LanguageContext";
 import { usePlatformModules, usePlatformUiCapability } from "../platform/ModuleContext";
 import { useEffectiveView } from "../platform/ViewContext";
 
-type NotificationSummary = {
-  unread: number;
-  show_unread_badge?: boolean;
-};
-
 type Props = {
   settings: ApiSettings;
   auth: AuthInfo | null;
@@ -35,7 +30,6 @@ export default function Titlebar({ settings, auth, onAuthChange, maintenanceMode
   const [loginOpen, setLoginOpen] = useState(false);
   const [switchingTenantId, setSwitchingTenantId] = useState<string | null>(null);
   const [tenantError, setTenantError] = useState("");
-  const [unreadNotificationCount, setUnreadNotificationCount] = useState(0);
   const accountRef = useRef<HTMLDivElement>(null);
   const tenantRef = useRef<HTMLDivElement>(null);
   const { translateText } = usePlatformLanguage();
@@ -55,7 +49,19 @@ export default function Titlebar({ settings, auth, onAuthChange, maintenanceMode
   "system:tenants:suspend"]
   );
   const showTenantControl = Boolean(activeTenant && (canSwitchTenant || canAdministerTenants));
+  const showContextSelectors = Boolean(
+    auth && ((activeTenant && showTenantControl) || ViewSelector)
+  );
   const notificationsAvailable = modules.some((module) => module.id === "notifications" && module.routes?.some((route) => route.path === "/notifications"));
+  const notificationSummary = useSharedNotificationSummary(settings, {
+    enabled: Boolean(auth && notificationsAvailable),
+    scopeKey: "current-session",
+    intervalMs: 60_000,
+    refreshKey: `${activeTenant?.id ?? ""}:${auth?.user?.id ?? ""}`
+  }).summary;
+  const unreadNotificationCount = notificationSummary?.show_unread_badge === false ?
+    0 :
+    Math.max(0, Number(notificationSummary?.unread) || 0);
   const notificationBadgeLabel = unreadNotificationCount > 99 ? "99+" : String(unreadNotificationCount);
 
   useEffect(() => {
@@ -72,41 +78,6 @@ export default function Titlebar({ settings, auth, onAuthChange, maintenanceMode
     return () => window.removeEventListener("mousedown", onPointerDown);
   }, []);
 
-  useEffect(() => {
-    if (!auth || !notificationsAvailable) {
-      setUnreadNotificationCount(0);
-      return;
-    }
-
-    let cancelled = false;
-    async function refreshNotificationSummary() {
-      try {
-        const summary = await apiFetch<NotificationSummary>(settings, "/api/v1/notifications/summary", { cache: "no-store" });
-        if (!cancelled) {
-          setUnreadNotificationCount(summary.show_unread_badge === false ? 0 : Math.max(0, Number(summary.unread) || 0));
-        }
-      } catch (error) {
-        if (!cancelled) {
-          setUnreadNotificationCount(0);
-        }
-        if (!isApiError(error, 401, 403, 404)) {
-          console.error("Failed to load notification summary", error);
-        }
-      }
-    }
-
-    void refreshNotificationSummary();
-    const intervalId = window.setInterval(refreshNotificationSummary, 60_000);
-    window.addEventListener("focus", refreshNotificationSummary);
-    window.addEventListener("govoplan:notifications-changed", refreshNotificationSummary);
-    return () => {
-      cancelled = true;
-      window.clearInterval(intervalId);
-      window.removeEventListener("focus", refreshNotificationSummary);
-      window.removeEventListener("govoplan:notifications-changed", refreshNotificationSummary);
-    };
-  }, [activeTenant?.id, auth?.user?.id, notificationsAvailable, settings.accessToken, settings.apiBaseUrl, settings.apiKey]);
-
   function handleLogin(response: LoginResponse) {
     onAuthChange(response, "");
   }
@@ -185,8 +156,10 @@ export default function Titlebar({ settings, auth, onAuthChange, maintenanceMode
         </button>
       }
 
-      {auth && activeTenant && showTenantControl &&
-      <div className="tenant-selector" ref={tenantRef}>
+      {auth && showContextSelectors &&
+      <div className="titlebar-context-selectors">
+        {activeTenant && showTenantControl &&
+        <div className="tenant-selector" ref={tenantRef}>
           <span className="tenant-label">{translateText("i18n:govoplan-core.tenant_label_prefix")}</span>
           {canSwitchTenant ?
         <>
@@ -218,13 +191,15 @@ export default function Titlebar({ settings, auth, onAuthChange, maintenanceMode
         <strong>{activeTenant.name}</strong>
         }
         </div>
+        }
+        {ViewSelector &&
+        <ViewSelector settings={settings} auth={auth} projection={projection} />
+        }
+      </div>
       }
 
       <div className="titlebar-spacer" />
 
-      {auth && ViewSelector &&
-      <ViewSelector settings={settings} auth={auth} projection={projection} />
-      }
       <LanguageMenu />
       <HelpMenu auth={auth} />