Show battle prompt keyboard hints

src/game/scenes/BattleScene.ts

@@ -15848,11 +15848,11 @@ export class BattleScene extends Phaser.Scene {
     this.turnPromptSecondaryAction = secondaryAction;
     const buttonWidth = 136;
     const buttons = [
-      { label: primaryLabel, x: left + 119, primary: true },
-      { label: secondaryLabel, x: left + 269, primary: false }
+      { label: primaryLabel, keyHint: 'Enter', x: left + 119, primary: true },
+      { label: secondaryLabel, keyHint: 'Esc', x: left + 269, primary: false }
     ];
 
-    buttons.forEach(({ label, x, primary }) => {
+    buttons.forEach(({ label, keyHint, x, primary }) => {
       const bg = this.add.rectangle(x, top + 116, buttonWidth, 36, 0x1a2630, 0.95);
       bg.setDepth(41);
       bg.setStrokeStyle(1, primary ? palette.gold : palette.blue, 0.72);
@@ -15873,6 +15873,16 @@ export class BattleScene extends Phaser.Scene {
       text.setInteractive({ useHandCursor: true });
       text.on('pointerdown', () => (primary ? this.activateTurnPromptPrimaryAction(true) : this.activateTurnPromptSecondaryAction(true)));
       this.turnPromptObjects.push(text);
+
+      const hint = this.add.text(x, top + 143, keyHint, {
+        fontFamily: '"Malgun Gothic", "Noto Sans KR", sans-serif',
+        fontSize: '10px',
+        color: primary ? '#cdbb8a' : '#91a7bd',
+        fontStyle: '700'
+      });
+      hint.setOrigin(0.5);
+      hint.setDepth(42);
+      this.turnPromptObjects.push(hint);
     });
 
     void message;