- Fix format-parity divergences in 6 tools so content[] and
  structuredContent carry the same data. Affects find-eligible,
  search-studies, get-study-count, get-field-definitions,
  get-study-record, get-field-values.
- Bump @cyanheads/mcp-ts-core 0.5.0 → 0.5.3 (format-parity linter,
  Docs Sync devcheck, server.json cross-validation).
- Sync scaffold scripts (adds check-docs-sync.ts) and 6 skills from
  the framework.