Add scripted trainer battle foundation and native move AI

docs/ARCHITECTURE.md

@@ -48,4 +48,4 @@ Asset caches and the ROM reader remain in memory for lazy extraction. Neither RO
 
 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.
 
-`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; no production map has encounters enabled yet. 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.
+`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. Scripted single-Pokémon trainer battles share that core, with ROM trainer decoders and explicit AI support checks; test fixtures exercise these without opening new production maps. 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.

docs/NATIVE_PORT.md

@@ -24,7 +24,7 @@ These paths refer to the pinned [PRET source](https://github.com/pret/pokecrysta
 | Native module                    | PRET reference                                                                                                                 | Evidence and limits                                                                                                                                                                                                                     |
 | -------------------------------- | ------------------------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `game/rom/lz.ts`                 | `home/decompress.asm`                                                                                                          | All LZ command types have unit vectors; six tilesets match original ASM execution byte-for-byte.                                                                                                                                        |
-| `game/rom/assets.ts` maps/events | `data/maps/maps.asm`, `data/maps/attributes.asm`, `data/maps/scenes.asm`, `data/maps/landmarks.asm`, `macros/scripts/maps.asm` | Any map header in the ROM's 26 groups decodes; only the six ported maps can be entered. Location names, scene-variable owners and connection offsets come from the ROM.                                                                 |
+| `game/rom/assets.ts` maps/events | `data/maps/maps.asm`, `data/maps/attributes.asm`, `data/maps/scenes.asm`, `data/maps/landmarks.asm`, `macros/scripts/maps.asm` | Any map header in the ROM's 26 groups decodes; only maps explicitly listed in NATIVE_MAPS can be entered. Location names, scene-variable owners and connection offsets come from the ROM.                                                                 |
 | Tiles/palettes                   | `home/map.asm`, `engine/gfx/color.asm`, `engine/tilesets/mapgroup_roofs.asm`                                                   | Graphics match rebuilt reference bytes. Connected maps draw beyond the edges with the current tileset, like the original strips. Terrain animation and other special palettes pending.                                                  |
 | Sprites/rendering                | `data/sprites/sprites.asm`, `data/sprites/facings.asm`, `data/sprites/emotes.asm`                                              | Chris/Kris, standard NPCs, emote bubbles and jump shadows decoded. Walking frames follow `SetFacingStepAction`. Dynamic Pokémon icons and room decorations pending.                                                                     |
 | `game/world/world.ts`            | `engine/overworld/events.asm`, `player_movement.asm`, `warp_connection.asm`, `data/collision/collision_permissions.asm`        | 30 Hz overworld ticks, 8-tick walks, 16-tick ledge jumps, directional mats, animated door/stair exits, connection coordinates, events, scenes and callbacks. NPC random walks and spins follow `HandleNPCStep`. Surfing remains absent; turn timing still needs comparison. |
@@ -67,6 +67,14 @@ Native production is `dist/`; the optional reference output is `dist-reference/`
 
 Native saves are version 3. Version 2 added scene values by owning map, phone contacts, the weekday offset and DST flag, and positions of objects that scripts moved on the current map. Version 3 adds the player ID, party, bag, Pokédex seen/caught sets and money. Early version-3 backups without money receive the original starting balance; explicitly invalid balances are rejected. Restores recompute each Pokémon's stats from its DVs and reject any mismatch, and check every item against its ROM pocket. Older saves migrate with new-game defaults; a missing player ID is drawn as a new game draws it. Objects are restored from the save on continue, and only the TILES callback runs, as in `MapSetupScript_Continue`.
 
+## Scripted trainer battle foundation
+
+`game/rom/trainers.ts` decodes `TrainerGroups`, `TrainerClassAttributes`, `TrainerClassNames`, `TrainerClassDVs` and map trainer headers. Tests cover all 542 ROM records across 67 classes; CAL2 construction refuses its SRAM-dependent Mystery Gift party.
+
+`game/battle/ai.ts` translates `AIChooseMove`, `AI_Redundant` and the Basic, Setup, Types, Offensive, Cautious and Status layers. It preserves the original random tie selection and known redundancy quirks. Smart, Opportunist, Aggressive and Risky remain refused, including the rival's AI. Synthetic scoring vectors establish the tested branches; original-engine AI execution parity is still pending.
+
+`loadtrainer`, `winlosstext` and `startbattle` now run single-Pokémon trainer battles through the existing battle UI. Tests cover Joey's ROM party/text/reward, RUN refusal, trainer experience, Amulet Coin, CANLOSE behavior, money limits, transactional rollback and midbattle restore. Chromium and WebKit exercise the UI with a test-only script. Production map gates are unchanged. Trainer items, party switching, sight lines, trainer-object interaction and the rival round trip remain unported.
+
 ## Next slice
 
 Route 29 and Cherrygrove are enabled with item balls, fruit trees and the daily reset, the Pokémon Center nurse and the recorded whiteout spawn. NPCs roam. Next: trainer sight lines and trainer battles, capture with the catching tutorial, and party, bag and Pokégear menus over the native models. Other specials stay refused until translated.

docs/PLAN.md

@@ -59,6 +59,14 @@ The emulator-backed prototype is now at `/reference.html`. The default applicati
 - NPCs roam as `HandleNPCStep` does: random walks (Y, X, XY) and slow/fast spins from `SpriteMovementData`, `CanObjectMoveInDirection` (side walls, land, objects' current and previous tiles, radius stored plus one, screen edge), random sleeps, freezing during text and `applymovement`, and deletion/respawn at home beyond the object window. Wandering positions are not saved; objects start from home on reload.
 - Still refused: the catching tutorial (`catchtutorial`) and Cherrygrove's rival scene, both reachable only after the Mystery Egg errand.
 
+## Implemented: first scripted trainer battle slice
+
+- ROM decoder for 542 trainer records across 67 classes, all four party formats, class names, DVs, rewards and map trainer headers. SRAM-dependent Mystery Gift parties remain refused.
+- Native move scoring for Basic, Setup, Types, Offensive, Cautious and Status, with deterministic tie selection. Other scoring layers remain refused.
+- Scripted single-Pokémon trainer battles support the challenge, sending out, RUN refusal, experience, win/loss text and prize money, including Amulet Coin. Script results, party changes and rewards commit together; interrupted saves replay from committed state.
+- Local-ROM tests and Chromium/WebKit tests exercise Youngster Joey through a test-only script. No new maps or trainer encounters are enabled in normal play.
+- Next: advanced AI, trainer party switching/items, trainer sight lines and normal trainer-object scripts, then the rival and Route 30 story. The rival remains refused because its AI is not yet translated.
+
 ## In progress: native battles
 
 The battle core, ROM tables, encounter hooks, battle UI and whiteout hooks are present. Unit tests cover wins, escape, loss, experience and move learning; reference tests compare damage and type effectiveness. Browser tests drive a test-only wild encounter through the real UI: victory with level-up and move learning, escape, whiteout, keyboard and on-screen D-pad menu navigation, mid-battle backup restore, and rollback of unsupported effects. Real Route 29 encounters now use the ROM's encounter tables. Capture, switching, items in battle, trainer battles and the rest of the opening quest remain unfinished.