Add battle fighter damage/heal cutscene items, wire up battle results

BATTLE_FIGHTER_DAMAGE/BATTLE_FIGHTER_HEAL let a move's own cutscene
apply damage/healing to "target" or "user", resolved from
BATTLE_FIGHTER_POS_TARGET/USER sentinels against the current action by
battleStateExecutingInit. fire/slash now call BATTLE_FIGHTER_DAMAGE on
their target.

BATTLE_POST_MOVE checks fighter health after each move and sets
BATTLE.result (now a real field, previously commented out) to
win/loss, transitioning into BATTLE_STATE_WON/LOST; fleeing sets
BATTLE_RESULT_FLED. All three end states now show a textbox before
moving on to BATTLE_STATE_ENDING.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

assets/cutscenes/battle/moves/fire.jsonc

@@ -11,6 +11,11 @@
     },
     {
       "type": "MODAL_CLOSE"
+    },
+    {
+      "type": "BATTLE_FIGHTER_DAMAGE",
+      "fighter": "target",
+      "amount": 12
     }
   ]
 }