feat: add visual animation when banking scores in Farkel

Refactor bank() to return bankable amount instead of mutating state,
enabling the UI layer to handle score updates and display a floating
+score animation that slides to the player's score pad. Applies to
both human and AI turns.

public/src/games/farkel/FarkelGame.js

@@ -559,8 +559,13 @@ export default class FarkelGame extends Phaser.Scene {
     if (this.busy || !this.isHumanTurn()) return;
     if (this.gs.phase === 'awaitPick' && !this.commitSelection()) return;
     if (this.gs.phase !== 'awaitDecision') return;
-    bank(this.gs);
+    const seat = this.gs.current;
+    const { bankable } = bank(this.gs);
     playSound(this, SFX.PENCIL_WRITE);
+    if (bankable > 0) {
+      await this.animateBank(seat, bankable);
+      this.gs.players[seat].score += bankable;
+    }
     this.render();
     this.advance();
   }
@@ -629,8 +634,12 @@ export default class FarkelGame extends Phaser.Scene {
       await this.delay(360);
       if (decideReroll(this.gs, skill)) continue;
       const seat = this.gs.current;
-      bank(this.gs);
+      const { bankable } = bank(this.gs);
       playSound(this, SFX.PENCIL_WRITE);
+      if (bankable > 0) {
+        await this.animateBank(seat, bankable);
+        this.gs.players[seat].score += bankable;
+      }
       if (this.gs.players[seat].score >= 1000) {
         this.portraitCtrls[seat]?.controller?.playEmotion?.('happy');
       }
@@ -659,6 +668,37 @@ export default class FarkelGame extends Phaser.Scene {
     });
   }
 
+  animateBank(seat, banked) {
+    return new Promise((resolve) => {
+      playSound(this, SFX.CASINO_WIN);
+      const row = this.scratchRows[seat];
+      const destX = PAPER_X + PAPER_W - 22;
+      const destY = row.y;
+
+      // Create floating text at dice area
+      const label = this.add.text(TRAY_CX, TRAY_CY, `+${banked}`, {
+        fontFamily: 'Righteous', fontSize: '80px', color: COLORS.goldHex,
+      }).setOrigin(0.5).setDepth(DEPTH.toast);
+
+      // Hold for 1 second
+      this.time.delayedCall(1000, () => {
+        // Animate to score pad
+        this.tweens.add({
+          targets: label,
+          x: destX,
+          y: destY,
+          scale: 0.5,
+          duration: 1000,
+          ease: 'Cubic.Out',
+          onComplete: () => {
+            label.destroy();
+            resolve();
+          },
+        });
+      });
+    });
+  }
+
   // ── game over ──────────────────────────────────────────────────────────────────
   showGameOver() {
     if (this.gameOverShown) return;

public/src/games/farkel/FarkelLogic.js

@@ -191,13 +191,17 @@ export function applySetAside(state, indices) {
 }
 
 // Bank the turn total (subject to the on-board minimum) and pass play.
+// Returns { bankable, scoreBefore, scoreAfter } so the caller can
+// handle score updates (e.g. for animations). Does NOT mutate state.score.
 export function bank(state) {
   const p = state.players[state.current];
   const t = state.turn;
   const bankable = (p.onBoard || t.kept >= ON_BOARD_MIN) ? t.kept : 0;
-  if (bankable > 0) { p.score += bankable; p.onBoard = true; }
+  const scoreBefore = p.score;
+  const scoreAfter = scoreBefore + bankable;
+  if (bankable > 0) p.onBoard = true;
   advanceTurn(state);
-  return state;
+  return { bankable, scoreBefore, scoreAfter };
 }
 
 // Forfeit the turn total and pass play.