Normalize artifact filenames and register new runs (#17)

Rename all output artifacts to their canonical case-id names
(mythos-craft.html / pelican-cycling.svg / skeleton-watch.html, with
-2 suffixes for variants) and drop the now-redundant "file" overrides
from the corresponding models/*.json runs.

Register new Claude Code runs for Opus 4.6 and 4.7 (new model JSONs),
add the GPT-5.5 Pro skeleton-watch run, and regenerate the README
registry tables. Remove stray .DS_Store files from outputs/.

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

models/claude-opus-4-6-cursor.json

@@ -14,7 +14,6 @@
       "contributor": "Nagi-ovo"
     },
     "pelican-cycling": {
-      "file": "pelican-bicycle.svg",
       "note": {
         "zh": "在 Cursor CLI 中以 Claude Opus 4.6（Max 思考配额）一次生成；本页为未经修改的原始产出。",
         "en": "Generated in one shot by Claude Opus 4.6 (Max effort) inside Cursor CLI; unmodified original output."