Update a resource, using a valid management key. The request replaces the whole resource: load it, change the fields, and send it back with its version unchanged. The type and uri cannot be changed. A stale version fails with Resource not found (E074805), so reload the resource and retry. On a resource managed by an agent gateway (tagged gateway), the connection scopes come from the gateway routes and only their optional flag can be changed. On an MCP server (type mcp), dynamicRegistrationSettings.issuerType and dynamicRegistrationSettings.overrideProjectSettings keep their stored values when omitted.