feat(12-04): tender-radar-api client — notification-pref + instantAlert

- fetchNotificationPref/saveNotificationPref for GET/PUT
  /modules/tender-radar/notification-pref (NOTIFY-01)
- SavedSearch/Create/UpdateSavedSearchPayload now carry instantAlert
  (NOTIFY-02, D-04)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/web/src/lib/tender-radar-api.ts

@@ -213,11 +213,15 @@ export async function setTriage(
  * deadlineFrom/To, openOnly, valueMin/Max, includeNullValue, sort, favOnly)
  * — see SavedSearchBar.tsx's serialize/deserialize helpers for the
  * round-trip contract.
+ *
+ * `instantAlert` (Plan 12-04, NOTIFY-02, D-04): per-profile Sofort-Alert
+ * toggle, default false — set via createSavedSearch/updateSavedSearch.
  */
 export interface SavedSearch {
   id: string;
   name: string;
   filters: Record<string, unknown>;
+  instantAlert: boolean;
   createdAt: string;
   updatedAt: string;
 }
@@ -226,12 +230,14 @@ export interface SavedSearch {
 export interface CreateSavedSearchPayload {
   name: string;
   filters: Record<string, unknown>;
+  instantAlert?: boolean;
 }
 
 /** Payload accepted by PATCH /modules/tender-radar/saved-searches/:searchId. */
 export interface UpdateSavedSearchPayload {
   name?: string;
   filters?: Record<string, unknown>;
+  instantAlert?: boolean;
 }
 
 /**
@@ -295,3 +301,43 @@ export async function deleteSavedSearch(id: string): Promise<void> {
   );
   if (!res.ok) throw new Error('Failed to delete saved search');
 }
+
+/**
+ * This user's digest interval preference (Plan 12-04, NOTIFY-01, D-01/D-03).
+ * Per-user, NOT per-profile — the backend derives userId from the auth
+ * cookie, this client never sends a userId.
+ */
+export interface NotificationPref {
+  digestInterval: 'daily' | 'weekly' | 'off';
+}
+
+/**
+ * Fetch this user's digest interval preference. Defaults to 'daily' on the
+ * backend when no row exists yet (D-01) — this client just relays whatever
+ * the backend returns.
+ * GET /modules/tender-radar/notification-pref
+ */
+export async function fetchNotificationPref(): Promise<NotificationPref> {
+  const res = await fetch(`${API_URL}/modules/tender-radar/notification-pref`, {
+    credentials: 'include',
+  });
+  if (!res.ok) throw new Error('Failed to fetch notification preference');
+  return res.json();
+}
+
+/**
+ * Save this user's digest interval preference.
+ * PUT /modules/tender-radar/notification-pref
+ */
+export async function saveNotificationPref(
+  digestInterval: NotificationPref['digestInterval'],
+): Promise<NotificationPref> {
+  const res = await fetch(`${API_URL}/modules/tender-radar/notification-pref`, {
+    method: 'PUT',
+    headers: { 'Content-Type': 'application/json' },
+    credentials: 'include',
+    body: JSON.stringify({ digestInterval }),
+  });
+  if (!res.ok) throw new Error('Failed to save notification preference');
+  return res.json();
+}