Automatically fix qBittorrent listening socket errors

[Aldaviva]

Problem

Every once in a while, qBittorrent randomly gets itself wedged and halts all traffic until you either restart the program or change the listening port. When this happens, the status bar health icon is a red globe (instead of green) and the log shows the following message (repeated several times):

7/10/2024 2:11 p - Failed to listen on IP. IP: "XXX.XXX.XXX.XXX". Port: "TCP/53708". Reason: "The requested address is not valid in its context"

Proposed solution

1. Periodically check if qBittorrent is running
2. If it's running, poll the web API to get the connection status. The connection_status key can have values connected, firewalled, and disconnected.

   GET http://localhost:8080/api/v2/transfer/info HTTP/1.1
   
   HTTP/1.1 200 OK
   Content-Type: application/json
   
   {
       "connection_status": "connected",
       "dht_nodes": 288,
       "dl_info_data": 119417236972,
       "dl_info_speed": 23819,
       "dl_rate_limit": 0,
       "up_info_data": 16199052905,
       "up_info_speed": 748749,
       "up_rate_limit": 0
   }

3. If the connection status is not connected, change the listening port to a different value, then change it back to the correct value.

[Aldaviva]

Every 3 minutes, PortForwardingService will check if qBittorrent is running and, if so, its connection status. If it's running and the connection status is not connected, it will temporarily change the qBittorrent listening port to 1 above the current PIA forwarded port, then to the correct PIA forwarded port again.

[Aldaviva]

This actually worked.