fix(journey): album photos, select-all, heading/hr fixes, dark mode

- Load actual album photos instead of date-range search fallback
  (new GET /albums/:id/photos for Immich + Synology)
- Add select all / deselect all toggle in photo picker
- Normalize Markdown headings to plain text in journal stories
- Fix setext headings (---) rendering as hr instead of h2
- Add remark-breaks for proper line break rendering
- Fix pros/cons dark mode gradient backgrounds
- i18n: selectAll/deselectAll in 14 languages

server/src/routes/memories/immich.ts

@@ -13,6 +13,7 @@ import {
   searchPhotos,
   streamImmichAsset,
   listAlbums,
+  getAlbumPhotos,
   syncAlbumAssets,
   getAssetInfo,
   isValidAssetId,
@@ -113,6 +114,13 @@ router.get('/albums', authenticate, async (req: Request, res: Response) => {
   res.json({ albums: result.albums });
 });
 
+router.get('/albums/:albumId/photos', authenticate, async (req: Request, res: Response) => {
+  const authReq = req as AuthRequest;
+  const result = await getAlbumPhotos(authReq.user.id, req.params.albumId);
+  if (result.error) return res.status(result.status!).json({ error: result.error });
+  res.json({ assets: result.assets });
+});
+
 router.post('/trips/:tripId/album-links/:linkId/sync', authenticate, async (req: Request, res: Response) => {
   const authReq = req as AuthRequest;
   const { tripId, linkId } = req.params;

server/src/routes/memories/synology.ts

@@ -7,6 +7,7 @@ import {
     getSynologyStatus,
     testSynologyConnection,
     listSynologyAlbums,
+    getSynologyAlbumPhotos,
     syncSynologyAlbumLink,
     searchSynologyPhotos,
     getSynologyAssetInfo,
@@ -77,6 +78,11 @@ router.get('/albums', authenticate, async (req: Request, res: Response) => {
     handleServiceResult(res, await listSynologyAlbums(authReq.user.id));
 });
 
+router.get('/albums/:albumId/photos', authenticate, async (req: Request, res: Response) => {
+    const authReq = req as AuthRequest;
+    handleServiceResult(res, await getSynologyAlbumPhotos(authReq.user.id, req.params.albumId));
+});
+
 router.post('/trips/:tripId/album-links/:linkId/sync', authenticate, async (req: Request, res: Response) => {
     const authReq = req as AuthRequest;
     const { tripId, linkId } = req.params;