Implement Retire HoF (Gauntlet) rule enforcement for genlockes

When retireHoF is enabled, surviving HoF Pokemon and their evolutionary
families are retired at leg advancement and treated as duplicates in all
subsequent legs — both in the encounter modal and bulk randomize.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/src/app/schemas/run.py

@@ -33,6 +33,7 @@ class RunGenlockeContext(CamelModel):
     leg_order: int
     total_legs: int
     is_final_leg: bool
+    retired_pokemon_ids: list[int] = []
 
 
 class RunDetailResponse(RunResponse):