Move territory from whole-country (ISO_A3) to individual sub-region id
granularity (PR 3 of #16):
- new server/regions.ts (turf-free): loadRegions (boot), expandTerritory
(game creation), migrateTerritoryToRegions (legacy games on db.load),
regionNamesFor / regionLabel (LLM prompt), graceful ISO_A3 fallback
- game creation expands each preset nation's ISO_A3 list to its sub-region
ids; pre-v0.19 saved games migrate transparently on read (idempotent)
- LLM contract: territoryChanges gain/lose sub-region ids (one region at a
time; gain moves out of the prior owner; lost-without-gainer = unowned);
user prompt carries a top-level regions reference table
({id: 'name (parent)'} over the state's territory ids)
- WorldMap: choropleth fill per sub-region (countries can split between
nations), ownership via properties.regionId through the shared
mapFeatureOwner, flash lights exactly the changed features
(featuresByRegionIds)
- deterministic stub: one region-level move per non-empty round (player
annexes the lexicographically-first region of the first other nation)
- tests: new server/regions.test.ts (real geo + fallback + seams);
map/engine tests re-pinned to region ids; scripts/regions.test.ts stays green
Measured full wwii-1939 user prompt (411 regions): ~24.7k chars / ~6.2k
tokens — far under the 80k frontier limit, so the full regions table is
always sent (no frontier-limited mode needed).
Part of #16
kamilkrzywda
fdf6eb236a