Equilateral mirror so the worker template carries the same flavor/cost
source of truth as KEY and meshscale.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Sync key_farm to Phase 0 + Phase 1 (consistency across surfaces)
Adds FarmStore.prune (Phase 0) and the ScalePolicy GPU flavor-picker (Phase 1)
so key_farm is identical with Ouroboros + meshscale. Additive only - the worker
runs neither prune nor the scaler, so behavior is unchanged; this purely prevents
farm-package divergence.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
