feat: rename "Daten" disk mount to "Medien" and consolidate Filme/Serien mount paths with explanatory comment

Add German comment explaining that Filme and Serien share the same host storage (/nesflix) and are made visible in the container via media mounts. Update mount_paths list to replace "Daten" label with "Medien" and combine Filme/Serien paths under single "Medien" label. Add dashboard-view CSS class with flex layout, min-height constraints, and increased disk-list gap for improved vertical

app.py

@@ -105,7 +105,9 @@ def system_metrics():
     total_memory = memory.get("MemTotal", 0)
     available_memory = memory.get("MemAvailable", memory.get("MemFree", 0))
     used_memory = max(0, total_memory - available_memory)
-    mount_paths = [("System", "/"), ("Daten", "/data"), ("Filme", "/media/filme"), ("Serien", "/media/serien")]
+    # Filme und Serien liegen auf demselben Host-Speicher (/nesflix) und
+    # werden im Container über die Medien-Mounts sichtbar gemacht.
+    mount_paths = [("System", "/"), ("Medien", "/media/filme"), ("Medien", "/media/serien")]
     disks, seen_devices = [], set()
     for label, path in mount_paths:
         try: