AAP-67740 Pass plugin_description through to CredentialType.description (#16364)

* Pass plugin_description through to CredentialType.description

Propagate the plugin_description field from credential plugins into the
CredentialType description when loading and creating managed credential
types, including updates to existing records.

Assisted-by: Claude

* Add unit tests for plugin_description passthrough to CredentialType

Tests cover load_plugin, get_creation_params, and
_setup_tower_managed_defaults handling of the description field.

Assisted-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: PabloHiro <palonso@redhat.com>

awx/main/tests/unit/models/test_credential.py

@@ -2,7 +2,11 @@
 
 import pytest
 
+from types import SimpleNamespace
+from unittest import mock
+
 from awx.main.models import Credential, CredentialType
+from awx.main.models.credential import CredentialTypeHelper, ManagedCredentialType
 
 from django.apps import apps
 
@@ -78,3 +82,53 @@ def test_credential_context_property_independent_instances():
     assert cred1.context == {'key1': 'value1'}
     assert cred2.context == {'key2': 'value2'}
     assert cred1.context is not cred2.context
+
+
+def test_load_plugin_passes_description():
+    plugin = SimpleNamespace(name='test_plugin', inputs={'fields': []}, backend=None, plugin_description='A test plugin')
+    CredentialType.load_plugin('test_ns', plugin)
+    entry = ManagedCredentialType.registry['test_ns']
+    assert entry.description == 'A test plugin'
+    del ManagedCredentialType.registry['test_ns']
+
+
+def test_load_plugin_missing_description():
+    plugin = SimpleNamespace(name='test_plugin', inputs={'fields': []}, backend=None)
+    CredentialType.load_plugin('test_ns', plugin)
+    entry = ManagedCredentialType.registry['test_ns']
+    assert entry.description == ''
+    del ManagedCredentialType.registry['test_ns']
+
+
+def test_get_creation_params_external_includes_description():
+    cred_type = SimpleNamespace(namespace='test_ns', kind='external', name='Test', description='My description')
+    params = CredentialTypeHelper.get_creation_params(cred_type)
+    assert params['description'] == 'My description'
+
+
+def test_get_creation_params_external_missing_description():
+    cred_type = SimpleNamespace(namespace='test_ns', kind='external', name='Test')
+    params = CredentialTypeHelper.get_creation_params(cred_type)
+    assert params['description'] == ''
+
+
+@pytest.mark.django_db
+def test_setup_tower_managed_defaults_updates_description():
+    registry_entry = SimpleNamespace(
+        namespace='test_ns',
+        kind='external',
+        name='Test Plugin',
+        inputs={'fields': []},
+        backend=None,
+        description='Updated description',
+    )
+    # Create an existing credential type with no description
+    ct = CredentialType.objects.create(name='Test Plugin', kind='external', namespace='old_ns')
+    assert ct.description == ''
+
+    with mock.patch.dict(ManagedCredentialType.registry, {'test_ns': registry_entry}, clear=True):
+        CredentialType._setup_tower_managed_defaults()
+
+    ct.refresh_from_db()
+    assert ct.description == 'Updated description'
+    assert ct.namespace == 'test_ns'