Add migration and documentation

docs/developer/README.md

@@ -405,3 +405,11 @@ This function is triggered by the post_save event on the User model, designed to
 1. For New Users: Upon the creation of a new user, it checks for an existing `Contact` by email. If no matching contact is found, it creates a new Contact using the user's details from Login.gov. If a matching contact is found, it associates this contact with the user. In cases where multiple contacts with the same email exist, it logs a warning and associates the first contact found.
 
 2. For Existing Users: For users logging in subsequent times, the function ensures that any updates from Login.gov are applied to the associated User record. However, it does not alter any existing Contact records.
+
+## Disable email sending (toggling the disable_email_sending switch)
+Feature switches are booleans that behave like environment variables that you can toggle through the DB.
+This switch globally disables our email sending feature. Using it is as simple as checking a box.
+1. On the app, navigate to `\admin`.
+2. Under models, click `Waffle switches`.
+3. Click the `disable_email_sending` record. This should exist by default, if not - create one with that name.
+4. (Important) Enable the checkbox for the field `Active`. This field overrides all other settings 

src/registrar/migrations/0097_create_groups_v13.py

@@ -0,0 +1,37 @@
+# This migration creates the create_full_access_group and create_cisa_analyst_group groups
+# It is dependent on 0079 (which populates federal agencies)
+# If permissions on the groups need changing, edit CISA_ANALYST_GROUP_PERMISSIONS
+# in the user_group model then:
+# [NOT RECOMMENDED]
+# step 1: docker-compose exec app ./manage.py migrate --fake registrar 0035_contenttypes_permissions
+# step 2: docker-compose exec app ./manage.py migrate registrar 0036_create_groups
+# step 3: fake run the latest migration in the migrations list
+# [RECOMMENDED]
+# Alternatively:
+# step 1: duplicate the migration that loads data
+# step 2: docker-compose exec app ./manage.py migrate
+
+from django.db import migrations
+from registrar.models import UserGroup
+from typing import Any
+
+
+# For linting: RunPython expects a function reference,
+# so let's give it one
+def create_groups(apps, schema_editor) -> Any:
+    UserGroup.create_cisa_analyst_group(apps, schema_editor)
+    UserGroup.create_full_access_group(apps, schema_editor)
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("registrar", "0096_waffleswitch"),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            create_groups,
+            reverse_code=migrations.RunPython.noop,
+            atomic=True,
+        ),
+    ]

src/registrar/utility/email.py

@@ -9,6 +9,7 @@ from email.mime.application import MIMEApplication
 from email.mime.multipart import MIMEMultipart
 from email.mime.text import MIMEText
 from waffle import switch_is_active
+from django.conf import settings
 
 
 logger = logging.getLogger(__name__)
@@ -34,7 +35,7 @@ def send_templated_email(
     context as Django's HTML templates. context gives additional information
     that the template may use.
     """
-    if switch_is_active("disable_email_sending"):
+    if switch_is_active("disable_email_sending") and not settings.IS_PRODUCTION:
         raise EmailSendingError("Could not send email. Email sending is disabled due to switch 'disable_email_sending'.")
 
     logger.info(f"An email was sent! Template name: {template_name} to {to_address}")