Add device enrollment API and agent protocol

Expose ITAM REST endpoints for agents, console GraphQL for device
management, and wire probod bootstrap with enrollment e2e coverage.

Signed-off-by: Ludovic Vielle <ludovic@probo.com>

pkg/server/jsonx/errors.go

@@ -42,3 +42,7 @@ func RenderNotFound(w http.ResponseWriter, err error) {
 func RenderBadRequest(w http.ResponseWriter, err error) {
 	httpserver.RenderError(w, http.StatusBadRequest, err)
 }
+
+func RenderUnauthorized(w http.ResponseWriter, err error) {
+	httpserver.RenderError(w, http.StatusUnauthorized, err)
+}