🪩 Score Pop Animation

### Description

Make score briefly pop or scale when incrementing.
Goal: micro-animation with state triggers.
Test: +1 visual bump on each food eaten.

### Proposed Solution

_No response_

### Screenshots / Mockups (optional)

_No response_

### Additional Context

_No response_

### Checklist

- [x] I searched existing issues for duplicates
- [ ] This issue includes enough detail to act on