feat: add configurable timezone for daily puzzle rotation with logging

app/api/daily/route.ts

@@ -5,13 +5,22 @@ const prisma = new PrismaClient();
 
 export async function GET() {
     try {
-        const today = new Date().toISOString().split('T')[0];
+        // Use timezone from environment variable (default: Europe/Berlin)
+        const timezone = process.env.TZ || 'Europe/Berlin';
+        const today = new Date().toLocaleDateString('en-CA', {
+            timeZone: timezone,
+            year: 'numeric',
+            month: '2-digit',
+            day: '2-digit'
+        }); // Format: "2025-11-21"
 
         let dailyPuzzle = await prisma.dailyPuzzle.findUnique({
             where: { date: today },
             include: { song: true },
         });
 
+        console.log(`[Daily Puzzle] Date: ${today}, Found existing: ${!!dailyPuzzle}`);
+
         if (!dailyPuzzle) {
             // Get all songs with their usage count
             const allSongs = await prisma.song.findMany({
@@ -54,6 +63,8 @@ export async function GET() {
                 },
                 include: { song: true },
             });
+
+            console.log(`[Daily Puzzle] Created new puzzle for ${today} with song: ${selectedSong.title} (ID: ${selectedSong.id})`);
         }
 
         if (!dailyPuzzle) {
@@ -63,7 +74,10 @@ export async function GET() {
         return NextResponse.json({
             id: dailyPuzzle.id,
             audioUrl: `/uploads/${dailyPuzzle.song.filename}`,
-            songId: dailyPuzzle.songId
+            songId: dailyPuzzle.songId,
+            title: dailyPuzzle.song.title,
+            artist: dailyPuzzle.song.artist,
+            coverImage: dailyPuzzle.song.coverImage ? `/uploads/covers/${dailyPuzzle.song.coverImage}` : null,
         });
 
     } catch (error) {