kgom-exact-mcp — endpoints:
  GET  /health             → health + Exact-auth status
  GET  /auth               → start Exact backend OAuth (eenmalig)
  GET  /oauth/callback     → Exact OAuth redirect-target
  GET  /authorize          → start MCP-client OAuth (claude.ai)
  GET  /callback           → Google OAuth redirect-target
  POST /mcp                → MCP JSON-RPC (Bearer token vereist)
  GET  /sse                → MCP SSE (Bearer token vereist)