- Allow spell chaining within a turn (Puzzle Quest rule): casting a spell
no longer ends your turn, enabling multiple casts per turn followed by a
gem swap to pass play.
- Add procedural spell-icon textures (shield, swords, bolt, flame, meteor,
thorn, poison, dagger, banner, leaf) for visual spell feedback.
- Implement combat animations: skull-match convergence strike, spell damage
fly-in, spell heal burst with particle ring, HP bar flash, and floating
damage/heal numbers.
- Refactor HP and mana updates into separate `updateHpBar` and `updateManaBar`
methods so mana reacts immediately while HP drains at animation climax.
- Defer stun application until the caster's turn actually ends.
- Update tutorial and verification tests to match the new turn-passing rules.