Register the Claude Code x Fable 5 Max combination as its own entry

The minecraft.html artifact is Fable 5 Max run inside Claude Code — a
different harness from the existing Claude Web App entry, so per the
model x harness x effort architecture it becomes a new combination
(claude-fable-5-code) rather than a variant. The validator now also
rejects loose files under outputs/<id>/ that no run declares, which is
how this artifact briefly slipped into the repo unregistered. OG count
refreshed (11 -> 12 ran).

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

models/claude-fable-5-code.json

@@ -0,0 +1,16 @@
+{
+  "label": "Claude Fable 5",
+  "vendor": "Anthropic",
+  "harness": "Claude Code",
+  "effort": "Max",
+  "order": 12,
+  "runs": {
+    "mythos-craft": {
+      "note": {
+        "zh": "在 Claude Code 中以 Claude Fable 5（Max 思考配额）一次生成，本页为未经修改的原始产出。与「Claude 网页版」条目同模型、不同 Harness——两个标签页并排即可对比同一模型在不同运行环境下的差异。",
+        "en": "Generated in one shot by Claude Fable 5 (Max effort) inside Claude Code; this page is the unmodified original output. Same model as the Claude Web App entry but a different harness — compare the two tabs to see how the environment shapes the result."
+      },
+      "contributor": "Nagi-ovo"
+    }
+  }
+}