Add the Johto and Kanto atlas to the Map tab

The Map tab draws the region's Town Map from the ROM with the player's
landmark, the visited flypoints as Fly destinations and the landmarks
whose maps are ported. Kanto opens with the Fly map's Indigo Plateau
rule. Landmark positions and flypoints are compared with the pinned
PRET source.

Closes #36

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/ARCHITECTURE.md

@@ -46,7 +46,7 @@ Scripts are generators that evaluate against a private draft and yield presentat
 
 Asset caches and the ROM reader remain in memory for lazy extraction. Neither ROMs nor extracted assets enter IndexedDB, the build or a backend. Vite blocks serving the root ROM and private reference checkout during development.
 
-The native viewport follows its available CSS dimensions and draws additional world tiles at a bounded pixel resolution. Beyond a map's edge it draws the connected map with the current tileset, as the original connection strips do, and the border block elsewhere. Resizing also redraws paused sessions. The local minimap caches terrain from the loaded map and updates its marker from the same world position used by the player; the Map tab shares that view. It is a current-area map, not a full region atlas. Leaving Game pauses the session and releases held input; returning requires explicit play. The reference player retains its own fixed-screen styling.
+The native viewport follows its available CSS dimensions and draws additional world tiles at a bounded pixel resolution. Beyond a map's edge it draws the connected map with the current tileset, as the original connection strips do, and the border block elsewhere. Resizing also redraws paused sessions. The local minimap caches terrain from the loaded map and updates its marker from the same world position used by the player; the Map tab shares that view. Below it, the Map tab draws the region atlas (`world/atlas.ts`): the ROM's Town Map with the player's landmark, the visited flypoints and the areas open in this port. Leaving Game pauses the session and releases held input; returning requires explicit play. The reference player retains its own fixed-screen styling.
 
 `game/battle` now holds the native battle core and ROM-backed battle tables. Browser tests cover the overworld-to-battle flow using a test-only encounter fixture; Route 29 uses ROM encounter tables. Trainer battles share that core, with ROM trainer decoders, the trainer's send-out and switch AI, and explicit AI support checks. Map trainers (sight and talk) are started by `game/world` and run the ROM's own trainer scripts. Battles receive the script's draft party, bag and Pokédex, so a catch, a thrown ball or a nickname commits only with the script that started the battle. Introduce future modules with working features: `game/audio`, then `features/link` and `features/walking`. Party and bag models live in `game/party`; scripts change them only on their draft state. Rules must not import UI/browser modules. Transports and step providers must not write directly into world state.