✨(backend) expose is_active field for Application in Django admin

Add minimal admin support to allow administrators to mark an
application account as inactive if it becomes rogue or compromised.

This capability was missing when the application concept was
initially introduced in the backend.

src/backend/core/admin.py

@@ -308,7 +308,7 @@ class ApplicationAdmin(admin.ModelAdmin):
 
     form = ApplicationAdminForm
 
-    list_display = ("id", "name", "client_id", "get_scopes_display")
+    list_display = ("id", "name", "client_id", "get_scopes_display", "is_active")
     fields = [
         "name",
         "id",
@@ -317,6 +317,7 @@ class ApplicationAdmin(admin.ModelAdmin):
         "scopes",
         "client_id",
         "client_secret",
+        "is_active",
     ]
     readonly_fields = ["id", "created_at", "updated_at"]
     inlines = [ApplicationDomainInline]