feat: Initial NPM MCP server implementation

- NpmClient with JWT auth and auto-refresh
- FastMCP server with 5 tools (list_proxy_hosts, get_proxy_host_details, get_system_health, search_audit_logs, list_certificates)
- Docker support with multi-stage build using uv
- Supports stdio and streamable HTTP transports
- GitHub Actions for tests and Docker builds

.dockerignore

@@ -0,0 +1,16 @@
+# Docker ignore - exclude unnecessary files from build context
+.venv/
+venv/
+__pycache__/
+*.py[cod]
+*.egg-info/
+.git/
+.gitignore
+.env
+*.md
+!README.md
+tests/
+.pytest_cache/
+.coverage
+.idea/
+.vscode/