Initial release: game-studio plugin for Claude Code

Repackaged from OpenAI's game-studio Codex plugin (MIT) for Claude Code.

Changes from upstream:
- Added .claude-plugin/plugin.json (Claude Code plugin manifest)
- Removed .codex-plugin/plugin.json (Codex CLI specific)
- Removed skills/*/agents/openai.yaml (Codex CLI specific)
- Added scripts/requirements.txt (Pillow dependency for sprite-pipeline)
- Added Chinese README with installation guide

references/phaser-architecture.md

@@ -0,0 +1,56 @@
+# Phaser Architecture
+
+This is the default 2D structure for the plugin.
+
+## Recommended module split
+
+```text
+src/
+  game/
+    simulation/
+      state.ts
+      systems/
+      rules/
+    content/
+      encounters/
+      items/
+      maps/
+    input/
+      actions.ts
+      bindings.ts
+    assets/
+      manifest.ts
+  phaser/
+    boot/
+    scenes/
+      BootScene.ts
+      MenuScene.ts
+      BattleScene.ts
+    view/
+      sprites/
+      fx/
+      camera/
+    adapters/
+      sceneBridge.ts
+  ui/
+    hud/
+    menus/
+    overlays/
+```
+
+## Responsibilities
+
+- `simulation/`: source of truth for rules and saveable state
+- `content/`: authored data and encounter configuration
+- `input/`: action map and physical control bindings
+- `assets/`: stable manifest keys and asset metadata
+- `phaser/scenes/`: scene orchestration, not game rules
+- `phaser/view/`: render and effect helpers
+- `ui/`: DOM HUD, menus, and narrative panels
+
+## Rules
+
+- Phaser scenes read from and write to the simulation through a defined bridge.
+- Game state changes should not depend on sprite or tween lifetime.
+- Camera behavior should be isolated from combat or movement rules.
+- Use DOM for dense text and settings surfaces.