URLs in Playlist inline bearbeiten (Edit-Button + Modal)

- Neue Route POST /admin/<site>/update-playlist-item/<screen>
- Bearbeiten-Button (✎) für URL-Items in admin.html + priority.html
- Modal mit URL + Zoom-Feld, Validierung und Speichern
- Grid um Edit-Spalte erweitert (28px|1fr|90px|80px|40px|50px|32px)

app.py

@@ -1575,6 +1575,45 @@ def save_playlist(site, screen):
     return "", 204
 
 
+# -------------------------------------------------
+# Admin: Playlist-Item bearbeiten (URL + Zoom)
+# -------------------------------------------------
+@app.route("/admin/<site>/update-playlist-item/<screen>", methods=["POST"])
+@site_access_required
+def update_playlist_item(site, screen):
+    """Aktualisiert URL und Zoom eines einzelnen Playlist-Items."""
+    data = request.get_json()
+    old_name = data.get("old_name")
+    new_url = data.get("new_url", "").strip()
+    zoom = data.get("zoom", 1.0)
+
+    if not is_url(new_url):
+        return jsonify({"error": "Ungültige URL"}), 400
+
+    try:
+        zoom = float(zoom)
+        if zoom <= 0:
+            zoom = 1.0
+    except (ValueError, TypeError):
+        zoom = 1.0
+
+    config = load_config()
+
+    if screen == "priority":
+        playlist = config.setdefault("priority", {}).setdefault("playlist", [])
+    else:
+        playlist = config["sites"][site]["screens"][screen].setdefault("playlist", [])
+
+    for i, item in enumerate(playlist):
+        name = playlist_item_name(item)
+        if name == old_name:
+            playlist[i] = {"url": new_url, "zoom": zoom}
+            save_config(config)
+            return jsonify({"success": True})
+
+    return jsonify({"error": "Item nicht gefunden"}), 404
+
+
 # -------------------------------------------------
 # Change-Password (für First-Login / Reset)
 # -------------------------------------------------