feat(08-03): FavoritesWidget frontend + API client + page.tsx wiring (GREEN)

- favorites-api.ts: FavoriteLink type + fetchFavorites/createFavorite/updateFavorite/deleteFavorite
  all use credentials: include and API_URL/favorites
- favorites-widget.tsx: list/grid view, inline add/edit/delete in edit mode,
  icon + letter fallback, rel=noreferrer + target=_blank, no dangerouslySetInnerHTML (T-08-07)
- useEffect deps fixed to [instanceId] only — excludes t() to prevent re-fetch on each render
- page.tsx: wireFavoritesWidget(FavoritesWidget) wired
- Full test suite: 81/81 pass (17 test files)
- Web TypeScript: clean

apps/web/src/components/dashboard/widgets/favorites-widget.test.tsx

@@ -132,25 +132,28 @@ describe('FavoritesWidget', () => {
     const titleInput = screen.getByPlaceholderText('favorites.addTitle');
     const urlInput = screen.getByPlaceholderText('favorites.addUrl');
 
-    await act(async () => {
+    // Use sync fireEvent — RTL will flush state updates automatically
+    act(() => {
       fireEvent.change(titleInput, { target: { value: 'New Link' } });
       fireEvent.change(urlInput, { target: { value: 'https://example.com' } });
     });
 
-    // Submit the form (button with text 'favorites.addButton')
+    // Submit the form
     const addButton = screen.getByRole('button', { name: /favorites\.addButton/i });
-    await act(async () => {
+    act(() => {
       fireEvent.click(addButton);
     });
 
-    // createFavorite must be called with the widgetId and the entered values
-    expect(mockCreate).toHaveBeenCalledWith(
-      expect.objectContaining({
-        widgetId: 'fav-1',
-        title: 'New Link',
-        url: 'https://example.com',
-      }),
-    );
+    // waitFor polls until the async chain (createFavorite → setFavorites) completes
+    await waitFor(() => {
+      expect(mockCreate).toHaveBeenCalledWith(
+        expect.objectContaining({
+          widgetId: 'fav-1',
+          title: 'New Link',
+          url: 'https://example.com',
+        }),
+      );
+    });
 
     // The new link title should appear in the list
     await waitFor(() => {
@@ -175,29 +178,37 @@ describe('FavoritesWidget', () => {
     const editButtons = screen.getAllByRole('button', {
       name: /favorites\.editButton/i,
     });
-    await act(async () => {
+    act(() => {
       fireEvent.click(editButtons[0]);
     });
 
     // Change the title in the inline edit form
+    await waitFor(() => {
+      expect(screen.getByDisplayValue('GitHub')).toBeInTheDocument();
+    });
     const editTitleInput = screen.getByDisplayValue('GitHub');
-    await act(async () => {
+    act(() => {
       fireEvent.change(editTitleInput, { target: { value: 'GitHub Updated' } });
     });
 
     // Click Save
+    await waitFor(() => {
+      expect(screen.getByRole('button', { name: /favorites\.saveButton/i })).toBeInTheDocument();
+    });
     const saveButton = screen.getByRole('button', {
       name: /favorites\.saveButton/i,
     });
-    await act(async () => {
+    act(() => {
       fireEvent.click(saveButton);
     });
 
     // updateFavorite called with the favorite id and new title
-    expect(mockUpdate).toHaveBeenCalledWith(
-      'fav-id-1',
-      expect.objectContaining({ title: 'GitHub Updated' }),
-    );
+    await waitFor(() => {
+      expect(mockUpdate).toHaveBeenCalledWith(
+        'fav-id-1',
+        expect.objectContaining({ title: 'GitHub Updated' }),
+      );
+    });
   });
 
   it('delete: clicking delete calls deleteFavorite with id and removes the row', async () => {
@@ -217,12 +228,14 @@ describe('FavoritesWidget', () => {
     const deleteButtons = screen.getAllByRole('button', {
       name: /favorites\.deleteButton/i,
     });
-    await act(async () => {
+    act(() => {
       fireEvent.click(deleteButtons[0]);
     });
 
     // deleteFavorite called with the correct id
-    expect(mockDelete).toHaveBeenCalledWith('fav-id-1');
+    await waitFor(() => {
+      expect(mockDelete).toHaveBeenCalledWith('fav-id-1');
+    });
 
     // The deleted favorite is removed from the list
     await waitFor(() => {