feat: JSON responses for list/search tools, ranked multi-term search …

…(v0.2.0) (#3)

- search_articles and list_repos now return structured JSON; content tools
  keep returning raw Markdown
- search_articles matches query terms individually (OR) and ranks by match
  count, so multi-word queries return relevant results instead of nothing
- fix repository links in package.json; bump to 0.2.0

feat: publish as @agentailor/mcp (npx) and add HTTP deploy path (#2)