Add antidote status cure item

docs/GODOT_4_6_MIGRATION.md

@@ -47,6 +47,7 @@ powershell -NoProfile -ExecutionPolicy Bypass -File tools\check_godot46_readines
 - Manual checkpoint save/load restores the expected current briefing without script errors.
 - A player unit can move, attack, wait, use a tactic, use an item, and equip compatible gear.
 - Poison Mist applies poison, poison ticks at the target team's phase start, and poison defeat immediately ends the battle when it satisfies a victory or defeat condition.
+- Antidote can cure poison and does not consume stock when used on a target without a matching status.
 - Enemy turn advances and AI acts.
 - Victory and defeat panels still appear.
 - Post-battle dialogue and post-battle choices still block progression until a choice is saved.