fix(synology): paginate all three album sources past 100 albums and tighten targetUserId type

- Extract _fetchAllSynologyAlbums helper that loops until the source is
  exhausted; listSynologyAlbums now uses it for personal, shared-out,
  and shared-with-me instead of a hard-capped single request of 100
- Make getSynologyAssetInfo targetUserId required (number, not number|undefined)
  to match every call site and eliminate an implicit any at the _requestSynologyApi
  boundary

server/src/db/migrations.ts

@@ -1629,6 +1629,11 @@ function runMigrations(db: Database.Database): void {
         )
       `);
     },
+    // Migration 104: Passphrase support for Synology shared-album links (#689)
+    () => {
+      try { db.exec('ALTER TABLE trip_album_links ADD COLUMN passphrase TEXT DEFAULT NULL'); } catch (err: any) { if (!err.message?.includes('duplicate column name')) throw err; }
+      try { db.exec('ALTER TABLE trek_photos ADD COLUMN passphrase TEXT DEFAULT NULL'); } catch (err: any) { if (!err.message?.includes('duplicate column name')) throw err; }
+    },
   ];
 
   if (currentVersion < migrations.length) {