feat: add diagnostic view and update URL routing for build probe in provider and relying party

relying_party/relying_party/urls.py

@@ -18,7 +18,7 @@ from django.contrib import admin
 from django.urls import include, path, re_path
 from django.views.static import serve
 
-from scripts.build_probe import build_probe_view
+from scripts.build_probe import build_probe_view, diag_view
 from spid_cie_oidc.entity.urls import urlpatterns as ta_urlpatterns
 from .visione_views import VisioneCompleteView, VisioneStartView
 
@@ -31,6 +31,7 @@ ADMIN_PATH = getattr(settings, 'ADMIN_PATH', 'admin/')
 urlpatterns = [
     path(f"{ADMIN_PATH}", admin.site.urls),
     path("__build", lambda request: build_probe_view("relying-party"), name="build_probe"),
+    path("__diag", lambda request: diag_view("relying-party"), name="diag_probe"),
     path("visione/start", VisioneStartView.as_view(), name="visione_start"),
     path("visione/complete", VisioneCompleteView.as_view(), name="visione_complete"),
     re_path('^static/(?P<path>.*)$',