[Feature]: Announcement for tracking Decapitation game progress

### Describe the Feature

Currently you have to search your team/the enemy team or remember every ACU killed to know the progress of the decapitation gamemode.

There could be different announcements for decapitation:
- When you are the last player with ACUs on a team
- When a player loses all ACUs, and how many ACUs remain on their team
- When an enemy loses all ACUs, and how many ACUs remain on their team
- When an enemy has the last ACUs on a team

At minimum, there should be an announcement when you are the last player with ACUs on your team.

### Expected Behavior

_No response_

### Screenshots

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### Additional context

_No response_