D-253 (resolves Q-105): the region owns transient clock-bound surface state — four phase terms (diurnal/tidal/weather/seasonal), memoized-by- bucket absolute-clock evaluation, edge-fuzzed per-tile inheritance, integer-deterministic (D-010), state-model-only (no gameplay/rendering). Discharges the T-1030/T-1078/T-1082 forward-contracts. Diurnal promoted to a first-class term (user-confirmed). Q-102 resolved-in-practice (D-246 voxel_mosaic + D-228 override stack); Q-103 + Q-109 deferred to Phase 5+ with dated triage notes. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>