feat(publicip): resilient public ip fetcher (#2518)

- `PUBLICIP_API` accepts a comma separated list of ip data sources, where the first one is the base default one, and sources after it are backup sources used if we are rate limited.
- `PUBLICIP_API` defaults to `ipinfo,ifconfigco,ip2location,cloudflare` such that it now has `ifconfigco,ip2location,cloudflare` as backup ip data sources.
- `PUBLICIP_API_TOKEN` accepts a comma separated list of ip data source tokens, each corresponding by position to the APIs listed in `PUBLICIP_API`.
- logs ip data source when logging public ip information
- assume a rate limiting error is for 30 days (no persistence)
- ready for future live settings updates
  - consider an ip data source no longer banned if the token changes
  - keeps track of ban times when updating the list of fetchers

internal/publicip/update.go

@@ -3,8 +3,10 @@ package publicip
 import (
 	"fmt"
 	"os"
+	"reflect"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/publicip/api"
 )
 
 func (l *Loop) update(partialUpdate settings.PublicIP) (err error) {
@@ -37,6 +39,15 @@ func (l *Loop) update(partialUpdate settings.PublicIP) (err error) {
 		}
 	}
 
+	if !reflect.DeepEqual(l.settings.APIs, updatedSettings.APIs) {
+		newFetchers, err := api.New(makeNameTokenPairs(updatedSettings.APIs), l.httpClient)
+		if err != nil {
+			return fmt.Errorf("creating fetchers: %w", err)
+		}
+
+		l.fetcher.UpdateFetchers(newFetchers)
+	}
+
 	l.settings = updatedSettings
 
 	return nil