bridgev2: add optional stop method for network connectors

bridgev2/bridge.go

@@ -216,6 +216,9 @@ func (br *Bridge) Stop() {
 	}
 	wg.Wait()
 	br.cacheLock.Unlock()
+	if stopNet, ok := br.Network.(StoppableNetwork); ok {
+		stopNet.Stop()
+	}
 	err := br.DB.Close()
 	if err != nil {
 		br.Log.Warn().Err(err).Msg("Failed to close database")

bridgev2/networkinterface.go

@@ -229,6 +229,11 @@ type NetworkConnector interface {
 	CreateLogin(ctx context.Context, user *User, flowID string) (LoginProcess, error)
 }
 
+type StoppableNetwork interface {
+	// Stop is called when the bridge is stopping, after all network clients have been disconnected.
+	Stop()
+}
+
 // DirectMediableNetwork is an optional interface that network connectors can implement to support direct media access.
 //
 // If the Matrix connector has direct media enabled, SetUseDirectMedia will be called