feat: add cs-dust2 React case with two model takes + react kind support

New case cs-dust2 (kind:react): a from-scratch React + three.js 5v5 Dust2 FPS.
Two takes registered: Claude Fable 5 / Claude Code / High (with a hand fix for a
64Hz fixed-step firing bug on high-refresh displays) and Claude Opus 4.8 /
Claude Code / Max (dust2-arena, one-shot). React cases commit source only; the
single file is built from source at deploy time. validate-data.ts now accepts a
React project directory as the declared artifact. AGENTS.md rewritten
English-only with React-case, bare-harness (no skills/plugins) and
artifact-anonymity rules.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

models/claude-opus-4-8-cc.json

@@ -46,6 +46,14 @@
         "en": "Generated in one shot by Claude Opus 4.8 (Max effort) inside Claude Code; unmodified original output. An interactive 3D skeleton mechanical watch on Three.js — orbit rotation, exploded view, highlighted part labels and a movement info panel, with escapement, balance wheel and other movement parts."
       },
       "contributor": "Nagi-ovo"
+    },
+    "cs-dust2": {
+      "file": "dust2-arena",
+      "note": {
+        "zh": "在 Claude Code 中以 Claude Opus 4.8（Max 思考配额）一次生成的完整 Vite + React 18 + three.js 工程，未经修改；本页为其构建产物（部署时由源码打包为单文件）。与 Claude Fable 5 条目同一道 cs-dust2 题、不同模型——可对比同题下两个模型的工程实现。",
+        "en": "A complete Vite + React 18 + three.js project generated in one shot by Claude Opus 4.8 (Max effort) in Claude Code, unmodified; this page is its build output (bundled from source into a single file at deploy time). Same cs-dust2 case as the Claude Fable 5 entry but a different model — compare how the two implement the same task."
+      },
+      "contributor": "Nagi-ovo"
     }
   }
 }