fix(simulation): address PR #142 review — 11 issues resolved
Rust fixes: D-218 Backwater complexity (moved to Full arm), priority
queue dispatch gated on thread saturation, panic→soft-fail in
name_index, duplicated LCG unified into atlas::rng module, misleading
Safety comment removed, D-210 SubBiomeVariant deferred to #948.
Schema/data fixes: atlas_city_positions table (D-211 persistence),
settlement_class column on atlas_city_names, per-body transaction
boundaries in import_province_boundaries, import_city_names.py added
to GENERATOR_SOURCES, Python perf documented.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>