docs(combat): harden spec after two critic passes
Adversarial review found no blockers but several serious issues; fixed:
- determinism: require vendoring reikhelm-core's order-independent, version-
stable Rng::fork (not DefaultHasher) + integer fixed-point internal state
with documented per-stage rounding; carve out chance()'s IEEE-deterministic
f64 compare as the sole hot-path exception
- pin a canonical within-tick resolution order (incl. step-0 controller
decisions in actor-id order) as a determinism invariant
- close internal-consistency dead-ends: fatigue clamp [0,max_vigor], cap=0 as
the explicit attrition-collapse trigger, regen floor + no-soft-lock rule,
fix inverted ceiling-damage verb
- enrich instrumentation (pre-mitigation damage, per-stage mitigation, blocked-
action + fail-reason, fill-flow accounting) + anti-turtle guardrail metric
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>