M2: бот и headless-прогон матчей

- PlayerView: проекция состояния, в которой боту видно только то,
  что видно живому игроку (своя рука, стол, размеры чужих рук, счётчики)
- BasicBot: политика из GAMEPLAY.md, полностью детерминированная
- Match: обёртка с состоянием и подпиской на события (её же возьмёт UI)
- runMatch: прогон матча без движка и без таймеров
- soak-тесты: 3500 полных матчей (боты и случайные легальные ходы,
  2-4 игрока), инварианты состояния проверяются после каждого действия
- npm run stats:bot — распределение исходов самоигры

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

docs/TECHNICAL.md

@@ -45,8 +45,9 @@ assets/
     core/                     PURE TS — no engine imports
       cards/                  Suit, Rank, Card, Deck
       rules/                  GameState, actions, events, the reducer
-      bot/                    PlayerView projection, BasicBot
-      util/                   seeded RNG, shuffle, assertions
+      bot/                    PlayerView projection, Bot contract, BasicBot
+      match/                  Match (stateful shell), runMatch (headless driver)
+      util/                   seeded RNG, shuffle
     modules/
       save/                   SaveManager, ISaveSection, StatsSection, storage
     app/                      Bootstrap, ServiceLocator, SceneRouter
@@ -54,7 +55,10 @@ assets/
       lobby/                  lobby screen controller
       game/                   match screen: hand, table, deck, animations
       common/                 reusable widgets, safe-area root
-tests/                        vitest specs against assets/scripts/core
+tests/
+  core/                       vitest specs against assets/scripts/core
+  support/                    position fixtures and the state invariant checker
+  tools/                      measuring tools, not part of the suite
 docs/                         specs, this file, plan, decisions
 local/                        scratch art storage; contents get consumed
 extensions/cocos-code-mode/   editor tool server
@@ -83,9 +87,16 @@ apply(state: GameState, action: Action): { state: GameState; events: GameEvent[]
 
 ## Bots
 
-A bot is a function `(view: PlayerView) => Action`. `PlayerView` is a projection
-of `GameState` containing only legitimately visible information. `BasicBot`
-implements the policy in [GAMEPLAY.md](GAMEPLAY.md) verbatim.
+A bot is `decide(view: PlayerView) => Action`. `PlayerView` is a projection of
+`GameState` containing only legitimately visible information — own hand, table,
+trump, opponents' hand *sizes*, deck and discard counts — plus the list of legal
+actions. `BasicBot` implements the policy in [GAMEPLAY.md](GAMEPLAY.md).
+
+`Match` wraps the reducer with the current state and an event subscription; the
+game screen and the headless `runMatch` driver both hold one. As a reference
+point, 5000 `BasicBot` self-play matches split roughly 43/43/14 between the two
+seats and draws, with the opening attacker losing about 37% of the time —
+`npm run stats:bot` reprints these.
 
 ## Savegame
 
@@ -114,7 +125,16 @@ Keys are explicit string constants, not class names — release builds minify.
 npm test
 ```
 
-Runs vitest over `tests/` against `assets/scripts/core`. No editor required.
+Runs vitest over `tests/core` against `assets/scripts/core`. No editor required.
+The soak specs play several thousand complete matches and re-check every state
+invariant after every single action, so a rule regression surfaces at the move
+that caused it.
+
+```bash
+npm run typecheck         # strict tsc over core/ and the tests
+npm run check:core-purity # fails if core/ ever imports the engine
+npm run stats:bot         # BasicBot self-play distribution, not a test
+```
 
 ### Driving the editor