Commit 5880f14 breaks compatibility of the Admin Port API by inserting an item in the middle of an enum.

Since this breaks all external libraries which connect to OpenTTD, I suggest to break the API again in 1.10.1 and to revert to the old enum values (by moving the new enum value to the end).

Reasoning:

• There are plenty of libraries written in various languages, which connect to the Admin Port. Most of them are unmaintained.
• Noone noticed the breakage during the RC period, so likely most won't notice it in 1.10.1 either. (if we give a poke to those who made a custom work around)
• In the long term, the API stays mostly compatible, so there will be no issues after 1.10.1.
• I do not know if API users rely on receiving NETWORK_ACTION_LEAVE for every player leaving the game. So another mitigation may be to send both NETWORK_ACTION_KICKED and NETWORK_ACTION_LEAVE (in this order).

I am not sure what API client @bjarnithor99 used when testing. Maybe you have some input as well.