test: make published skill checks self-contained - #3546

Summary

• make package-loader version tests use an explicit temporary HyperFrames ancestor fixture
• validate LUT preset IDs through the published matcher contract
• remove published-skill test dependencies on monorepo-only files

Tests

• isolated published fixture: 16/16 passed
• full skill helper suite: 553/553 passed
• oxfmt check: passed
• oxlint on changed files: passed
• quick_validate.py for all three affected skills: passed