feat(combat): high-rate cadence contracts

[f1cklepickle]

Why

High attack-speed values were being bottlenecked by input/event timing, one-frame mobile pulses, and animation-driven attack flow. Combat cadence needed to become runtime-authoritative so higher tiers produce real throughput without dropped swings, silent presentation caps, or repeated same-swing hit bugs.

What changed

• Moved attack cadence authority into PlayerAttackLoop so combat throughput scales beyond click cadence
• Reworked attack presentation so animation follows runtime cadence instead of owning it
• Switched Android/mobile fire input to held right-trigger intent instead of pulse/timer-driven cadence
• Added EditMode and PlayMode regressions for cadence ownership, mobile hold-fire, high-rate runtime cadence, and chained attack stability
• Fixed compressed high-rate hit delivery so short swings still land damage
• Fixed repeated same-swing hitbox damage discovered during validation
• Updated TEST_LOG and clarified hitbox runtime comments

How to test

1. Open MainPrototype
2. Press Play and verify low / normal / high attack-speed behavior still attacks correctly
3. Verify PC hold-fire and Android held-fire still work, and overlapping enemies only take one hit per swing
4. Run tests:
   • EditMode
   • PlayMode

Checklist

• Unit tests (EditMode) added or updated
• PlayMode test or manual validation included
• Demo scene updated (if player-visible) - N/A
• Prefab links, tags, and layers validated
• README / Docs touched (if applicable)

Related

• Closes feat(combat): support high attack rates beyond click cadence #148
• Closes refactor(anim): expose attack animation speed scaling contract #149
• Closes test(player): add PlayMode cadence coverage for high attack speeds #150
• Refs feat(visual): improve attack presentation readability at high swing speeds #156
• Refs feat(gameplay): add additional prototype weapons with distinct swing-speed tiers #157