refactor(slay-the-spire-like): update combat targeting and effect logic

Refactor combat targeting types and effect application logic in the
Slay the Spire-like sample.

- Update `getEffectTargets` to use `IntentEffectTarget` and more
  descriptive target keys (e.g., `eachEnemy`, `randomEnemy`).
- Update `promptMainAction` to use `enemy` instead of `single` for
  card target types.
- Refactor `addInstantEffectTriggers` to remove unused effect loading
  and improve enemy/card instantiation logic

src/samples/slay-the-spire-like/system/combat/effects.ts

@@ -10,7 +10,7 @@ import {
   CardData,
   CardEffectTarget,
   EffectData,
-  EffectTarget,
+  IntentEffectTarget,
 } from "@/samples/slay-the-spire-like/system/types";
 
 export function addEffect(
@@ -103,25 +103,25 @@ export function* getAliveEnemies(state: CombatState) {
 }
 
 export function* getEffectTargets(
-  target: CardEffectTarget | EffectTarget,
+  target: CardEffectTarget | IntentEffectTarget,
   game: CombatGameContext,
   targetId?: string,
   sourceEntityKey: "player" | string = "player",
 ) {
-  if (target === "all" || target === "team") {
+  if (target === "eachEnemy") {
     for (const enemy of getAliveEnemies(game.value)) {
       yield enemy;
     }
-  } else if (target === "self") {
+  } else if (target === "user") {
     const entity = getCombatEntity(game.value, sourceEntityKey);
     if (entity) yield entity;
   } else if (target === "player") {
     yield game.value.player;
-  } else if (target === "target") {
+  } else if (target === "eachTarget") {
     if (!targetId) return;
     const entity = getCombatEntity(game.value, targetId);
     if (entity) yield entity;
-  } else if (target === "random") {
+  } else if (target === "randomEnemy") {
     const aliveEnemies = [...getAliveEnemies(game.value)];
     if (aliveEnemies.length === 0) return;
     const index = game.rng.nextInt(aliveEnemies.length);