Connect local node
Local-node pairing lets a signed-in user sync desktop-backed routes, import local provider secrets into the hosted vault, and pull web-added providers back to the local node.
API clients can inspect the current node state at GET /api/local-node, import
catalog metadata with POST /api/local-node/catalog, migrate local provider
credentials with POST /api/local-node/providers/import, and reconcile web
providers with GET /api/local-node/sync.