Renamed general and mode constants and implemented a check to verify that constants are just defined ones over the whole repository

roles/web-app-pgadmin/config/main.yml

@@ -25,7 +25,7 @@ server:
         - "data:"
   domains:
     canonical:
-      - pgadmin.{{ primary_domain }}
+      - pgadmin.{{ PRIMARY_DOMAIN }}
 docker:
   services:
     database:

roles/web-app-pgadmin/users/main.yml

@@ -1,3 +1,3 @@
 users:
   administrator:
-    email:                "administrator@{{ primary_domain }}"
+    email:                "administrator@{{ PRIMARY_DOMAIN }}"