Closes #19713: Enable recording user messages in the change log (#19908)

* Add message field to ObjectChange model

* Set max length on changelog message

* Enable changelog messages for single object operations

* Fix tests

* Add changelog message support for bulk edit & bulk delete

* Cosmetic improvements to form fields

* Fix bulk operation templates

* Add message support for bulk import/update

* Add REST API support for changelog messages (WIP)

* Fix changelog_message assignment

* Enable changelog message support for bulk deletions

* Add documentation

* Fix changelog message support for VirtualChassis

* Add ChangeLoggingMixin to necesssary model forms

* Introduce get_random_string() utility function for tests

* Incorporate changelog messages for object view tests

* Incorporate changelog messages for object bulk view tests

* Add missing mixins for changelog message support

* Tweak test to generate expected number of change records

* Finish adding tests for changelog message functionality

* Misc cleanup

* Fixes #19956: Prevent duplicate deletion records from cascading deletions

* Tweak bulk deletion test to work around cascading deletions issue

* Correct API URL

netbox/core/migrations/0017_objectchange_message.py

@@ -0,0 +1,16 @@
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0016_job_log_entries'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='objectchange',
+            name='message',
+            field=models.CharField(blank=True, editable=False, max_length=200),
+        ),
+    ]