WOL-Plugin: UDP-Port used needs to be documented or configurable

[heitmanr]

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

The WOL-Plugin generates UDP-Packets "Magic Packets" to an undocumented default-port.

Most people would guess UDP-Port 9 or 7 to be used, but 40000 is it. => I've been spending a lot of time figuring this out.

Describe the solution you'd like

The imho best solution would be

• make the UDP-Port configurable (the Wireshark-Guys would chosse 40001 btw)

Describe alternatives you've considered

An improvement would be

• add a note about the UDP-Port in use to the Plugin-GUI.

Additional context If the OpnSense-Firewall would have the ability to forward directed-broadcasts, which could get controlled by firewall-rules, this plugin wouldn't be required, since a standard IP-Client could generate the WOL-Magic-Packets on it's own and and the firewall just would need to forward the WOL-Packet. Cisco implements this: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipapp/command/ipapp-xe-3se-3650-cr-book/ipapp-xe-3se-3850-cr-book_chapter_01.html#wp2181067464