CobblemonOptimizer

● Fix: Remove getActivePokemon() caching from PokemonBattleMixin

Problem: NoSuchElementException crash in Targetable.getOppositeOpponent() during battle start (Cobblemon 1.7.3 only).

Root cause: The mixin cached PokemonBattle.getActivePokemon() as a static snapshot (List.copyOf()). In Cobblemon 1.7.3, this method is a lazy iterable that evaluates on each call. During SwitchInstruction processing, the
cached snapshot became stale — the opponent's slot was in transition (old pokemon cleared, new one not yet assigned), so getOppositeOpponent() found no match and threw.

Fix: Removed the getActivePokemon() cache. Cobblemon's lazy iterable now evaluates in real-time, always reflecting current battle state. Other caches (sides, actors, players, isPvP/isPvN/isPvW) are unaffected — they don't change during instruction processing.

Why it only affects 1.7.3: Cobblemon 1.7.1 likely returned direct list references from getActivePokemon(), making the snapshot safe. 1.7.3 changed to a lazily computed iterable, breaking the snapshot approach.