Slice 2 (WIP): WarriorCone ability + class tests; Warrior path validated

Authored the WarriorCone AbilityDefinition (archetype Cone, dmg 22, range 2.2, ~130deg
arc, 22-tick cd) and added it to the gameplay subscene's AbilityDatabase (re-baked).
ClassTraitsTests cover the class->ability mapping + the asymmetric seed folds. 348/348.
Play-validated the Warrior end-to-end, server==client: AbilityRef=WarriorCone, 4 seeds,
eff MaxHP 130 / MoveSpd 5.1 / cone dmg 22 / coneRad 1.13; conns=1 (re-bake handshake
intact); zero runtime errors.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Assets/_Project/Subscenes/Gameplay.unity

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