Tweak buf breaking rules to be clearer about preferred mitigation when fields/enums are deleted.

[bleggett]

Also remove deprecated ZONE_STATE_EXITED

[github-actions]

The latest Buf updates on your PR. Results from workflow Buf CI / buf (pull_request).

Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	Feb 20, 2026, 5:22 PM

[bleggett]

@Sweetsurbhi88 this should quiet some of the breaking lints in #21, as well as more clearly indicating proper mitigation (reserve deleted field ID/names) going forward.

I left the deleted message breaking lint in place with no mitigation hint, because I think message deletion probably always needs an explicit callout.

[azenla]

I will note that ZONE_STATE_EXITED can still be used if the zone executable exits (though this should likely be removed and changed to key off of a panic or something)

[bleggett]

I will note that ZONE_STATE_EXITED can still be used if the zone executable exits (though this should likely be removed and changed to key off of a panic or something)

Yeah - that should unambiguously should map to the existing ZONE_STATE_FAILED in all cases, AFAICT