Call State Reconciliation

The ephemeral call maps are module-level and lost on restart, while the calls themselves are not: LiveKit is an external SFU, so participants stay connected through a deploy and only this side's picture of them goes (calls describes what that costs them). Reconciliation would restore the picture — ask LiveKit who is actually in each room through RoomServiceClient and rebuild the maps from the answer, or close the rooms on boot and make every client rejoin.

Why deferred

• The rebuild needs a trigger, and a poll is the wrong one — there is a listing to call but nothing native that fires on "this process just lost its state", and asking on a timer is exactly what no polling rules out.
• Closing the rooms on boot is a visible interruption to every live call, paid on every deploy, for a state loss that costs nothing while nobody is in a call.

Revisit when: calls run long enough, and deploys land often enough, that a call routinely spans one.