[LAN control] Support for selecting on which interface to send multicast packets

[DerekOverlock]

Please explain your feature request in a one or two sentences.

The current version of the homebridge-govee plugin will send multicast packets on the default gateway, it would be great if there was an option to select which interface these packets should be sent to and received from.

Is your feature request related to a problem? Please describe.

My use case: I'm running Homebridge on my Synology DSM220+ and using this plugin. I have two active interfaces on this system: bond0 (my aggregate LAN interface) and tun0 (my VPN connection). tun0 is selected as my default gateway as I want most services to use this connection. But, this breaks LAN control with this plugin as it will try to send multicast packets on this interface instead of the LAN.

Homebridge UI has a similar option in its settings for selecting which interface to bind mDNS to, it would be great if this plugin could offer a similar option.

Any particular Govee devices that this relates to?

Govee devices that support LAN control (in my case: H6046 and H6076)

Anything else?

Current workaround: I have created a scheduled task that will run when my Synology NAS starts up that adds a routing rule for multicast addresses to use the bond0 interface:

ip route add 239.255.255.250/32 dev bond0 # needs to run as root