feat: use sprite sheet for Old Maid card rendering

- Replace custom-drawn Old Maid card with sprite frame (frame 13)
- Load oldmaid-cards.png spritesheet in PreloadScene
- Rename GOFISH_CARD_FRAME to OLDMAID_CARD_FRAME for clarity

public/src/games/oldmaid/OldMaidGame.js

@@ -95,7 +95,7 @@ const SUIT_COLORS = {
   h: { fill: 0xfbe7e2, stroke: 0xc92a2a, glyph: '#c92a2a' },
   d: { fill: 0xfbe7e2, stroke: 0xc92a2a, glyph: '#c92a2a' },
 };
-const GOFISH_CARD_FRAME = { A: 0, '2': 1, '3': 2, '4': 3, '5': 4, '6': 5, '7': 6, '8': 7, '9': 8, T: 9, J: 10, Q: 11, K: 12 };
+const OLDMAID_CARD_FRAME = { A: 0, '2': 1, '3': 2, '4': 3, '5': 4, '6': 5, '7': 6, '8': 7, '9': 8, T: 9, J: 10, Q: 11, K: 12, OM: 13 };
 
 // ── Scene ───────────────────────────────────────────────────────────────────
 export default class OldMaidGame extends Phaser.Scene {
@@ -323,24 +323,10 @@ export default class OldMaidGame extends Phaser.Scene {
       return;
     }
 
-    // Special unmatched Old Maid card — distinct custom face.
+    const frame = OLDMAID_CARD_FRAME[card.rank];
-    if (card.isOldMaid) {
+    if (frame !== undefined && this.textures.exists('oldmaid-cards')) {
-      g.fillStyle(0x2c1a3a, 1);
-      g.fillRoundedRect(x, y, CARD_W, CARD_H, CARD_R);
-      g.lineStyle(3, 0xc678dd, 1);
-      g.strokeRoundedRect(x + 2, y + 2, CARD_W - 4, CARD_H - 4, CARD_R - 1);
-      container.add(g);
-      container.add(this.add.text(0, -8, '👵', { fontFamily: 'sans-serif', fontSize: '52px' }).setOrigin(0.5));
-      container.add(this.add.text(0, y + CARD_H - 22, 'OLD MAID', {
-        fontFamily: 'Righteous', fontSize: '13px', color: '#e6c8ff',
-      }).setOrigin(0.5));
-      return;
-    }
-
-    const frame = GOFISH_CARD_FRAME[card.rank];
-    if (frame !== undefined && this.textures.exists('gofish-cards')) {
       g.destroy();
-      container.add(this.add.image(0, 0, 'gofish-cards', frame).setDisplaySize(CARD_W, CARD_H).setOrigin(0.5));
+      container.add(this.add.image(0, 0, 'oldmaid-cards', frame).setDisplaySize(CARD_W, CARD_H).setOrigin(0.5));
       return;
     }
 

public/src/scenes/PreloadScene.js

@@ -88,6 +88,7 @@ export default class PreloadScene extends Phaser.Scene {
     this.load.spritesheet('dominion-tokens', '/assets/images/dominion-tokens.png', { frameWidth: 150, frameHeight: 150 });
     this.load.spritesheet('ttr-cards', '/assets/images/tickettoride-cards.png', { frameWidth: 270, frameHeight: 390 });
     this.load.spritesheet('gofish-cards', '/assets/images/gofish-cards.png', { frameWidth: 270, frameHeight: 390 });
+    this.load.spritesheet('oldmaid-cards', '/assets/images/oldmaid-cards.png', { frameWidth: 270, frameHeight: 390 });
     this.load.spritesheet('tab-icons', '/assets/images/tab-icons.png', { frameWidth: 128, frameHeight: 128 });
     this.load.spritesheet('game-icons', '/assets/images/game-icons.png', { frameWidth: 44, frameHeight: 44 });
   }