feat: add distribution files for Smithery, GitHub Action, and Claude Code Plugin

- Add Claude Code Plugin: plugin.json, .mcp.json, 3 slash commands, skill-builder agent skill
- Add GitHub Action: composite action.yml with 6 inputs/2 outputs, comprehensive README
- Add Smithery: publishing guide with namespace yusufkaraaslan/skill-seekers created
- Add render-mcp.yaml for MCP server deployment on Render
- Fix Dockerfile.mcp: --transport flag (nonexistent) → --http, add dynamic PORT support
- Update AGENTS.md to v3.3.0 with corrected test count and expanded CI section
- Allow distribution/claude-plugin/.mcp.json in .gitignore

Dockerfile.mcp

@@ -4,8 +4,8 @@
 FROM python:3.12-slim
 
 LABEL maintainer="Skill Seekers <noreply@skillseekers.dev>"
-LABEL description="Skill Seekers MCP Server - 25 tools for AI skills generation"
-LABEL version="2.9.0"
+LABEL description="Skill Seekers MCP Server - 35 tools for AI skills generation"
+LABEL version="3.3.0"
 
 WORKDIR /app
 
@@ -48,9 +48,10 @@ HEALTHCHECK --interval=30s --timeout=10s --start-period=10s --retries=3 \
 # Volumes
 VOLUME ["/data", "/configs", "/output"]
 
-# Expose MCP server port
-EXPOSE 8765
+# Expose MCP server port (default 8765, overridden by $PORT on cloud platforms)
+EXPOSE ${MCP_PORT:-8765}
 
 # Start MCP server in HTTP mode by default
-# Use --transport stdio for stdio mode
-CMD ["python", "-m", "skill_seekers.mcp.server_fastmcp", "--transport", "http", "--port", "8765"]
+# Uses shell form so $PORT/$MCP_PORT env vars are expanded at runtime
+# Cloud platforms (Render, Railway, etc.) set $PORT automatically
+CMD python -m skill_seekers.mcp.server_fastmcp --http --host 0.0.0.0 --port ${PORT:-${MCP_PORT:-8765}}