add skip route

app.py

@@ -347,6 +347,17 @@ async def api_volume():
     return jsonify(volume)
 
 
+@app.route("/api/skip", methods=["POST"])
+async def api_skip():
+    sock = await mpv_socket_open()
+    if sock is not None:
+        await mpv_socket_command(*sock, {"command": ["playlist-next"]})
+        sock[1].close()
+        await sock[1].wait_closed()
+
+    return "ok"
+
+
 @app.route("/api/upload", methods=["POST"])
 def upload_api():
     filename = request.form.get("filename")