Add credits to account in test setup for content generation, linking, and optimization tests

- Updated test cases in `test_universal_content_types.py`, `test_universal_content_linking.py`, and `test_universal_content_optimization.py` to initialize account credits for testing.
- Changed mock patch references to `run_ai_task` for consistency across tests.

backend/igny8_core/business/content/tests/test_universal_content_types.py

@@ -14,9 +14,12 @@ class UniversalContentTypesTests(IntegrationTestBase):
     
     def setUp(self):
         super().setUp()
+        # Add credits to account for testing
+        self.account.credits = 10000
+        self.account.save()
         self.service = ContentGenerationService()
     
-    @patch('igny8_core.business.content.services.content_generation_service.run_ai_task')
+    @patch('igny8_core.ai.tasks.run_ai_task')
     def test_product_content_generates_correctly(self, mock_run_ai_task):
         """
         Test: Product content generates correctly
@@ -55,7 +58,7 @@ class UniversalContentTypesTests(IntegrationTestBase):
         self.assertEqual(call_args[1]['function_name'], 'generate_product_content')
         self.assertEqual(call_args[1]['payload']['product_name'], 'Test Product')
     
-    @patch('igny8_core.business.content.services.content_generation_service.run_ai_task')
+    @patch('igny8_core.ai.tasks.run_ai_task')
     def test_service_pages_work_correctly(self, mock_run_ai_task):
         """
         Test: Service pages work correctly
@@ -94,7 +97,7 @@ class UniversalContentTypesTests(IntegrationTestBase):
         self.assertEqual(call_args[1]['function_name'], 'generate_service_page')
         self.assertEqual(call_args[1]['payload']['service_name'], 'Test Service')
     
-    @patch('igny8_core.business.content.services.content_generation_service.run_ai_task')
+    @patch('igny8_core.ai.tasks.run_ai_task')
     def test_taxonomy_pages_work_correctly(self, mock_run_ai_task):
         """
         Test: Taxonomy pages work correctly

backend/igny8_core/business/linking/tests/test_universal_content_linking.py

@@ -14,6 +14,9 @@ class UniversalContentLinkingTests(IntegrationTestBase):
     
     def setUp(self):
         super().setUp()
+        # Add credits to account for testing
+        self.account.credits = 10000
+        self.account.save()
         self.linker_service = LinkerService()
         
         # Create product content

backend/igny8_core/business/optimization/tests/test_universal_content_optimization.py

@@ -15,6 +15,9 @@ class UniversalContentOptimizationTests(IntegrationTestBase):
     
     def setUp(self):
         super().setUp()
+        # Add credits to account for testing
+        self.account.credits = 10000
+        self.account.save()
         self.optimizer_service = OptimizerService()
         
         # Create product content