Mirrors v1.2's BattleSessionDispatchTests but asserts on (target, frame,
noStock) routing tuples returned by ComputeFrames. Covers InitNetwork
ack, InitBattle/Loaded/Swap server-synthesized broadcasts (to the real
participant only in Scripted mode), TurnEnd forwarding to the scripted
bot, scripted-bot-emitted frames routing back to the real participant,
Retire/Kill BattleFinish path, and out-of-order frame drops.