Document session progress and current state

CLAUDE.md

@@ -141,3 +141,34 @@ Each development step follows this exact sequence:
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+
+## Current development state — updated 2026-04-25
+
+### OTIVM-I — complete
+- Fastify backend serving dist/ and save API on port 3000
+- Five trade routes, Ostia → Alexandria, all working
+- Journal entries firing on dispatch milestones
+- Otium/negotium mechanic working
+- Per-player save files in data/saves/ via 8-char hex token
+- Token displayed in UI — player can record it to resume on another device
+- 128 concurrent players supported
+
+### Navigation scaffold — complete
+- src/screens/ directory established
+- Game.jsx renamed to src/screens/Ledger.jsx
+- App.jsx manages screen state — ledger and map
+- Both screens stay mounted — no state lost on switch
+- Map screen shows placeholder — ready for OTIVM-II work
+
+### OTIVM-II — next
+- src/screens/Map.jsx to be created
+- Mediterranean rendered using H3 geometry
+- Five waypoints plotted using confirmed H3 res-5 IDs
+- Route lines drawn between waypoints
+- No interactivity required in first Map commit — visual only
+
+### Architecture decisions locked
+- H3 IDs on all waypoints — permanent, TESSERA-compatible
+- constants.js / gameState.js / api.js separation — permanent
+- Virtual screens via display:none — state preserved in browser
+- Save on meaningful events only — not on every tick