Fix all failing tests and pytest collection warnings

Fixed MagicMock comparison errors across multiple test suites by:
- Adding proper ModelCapabilities mocks with real values instead of MagicMock objects
- Updating test_auto_mode.py with correct provider mocking for model availability tests
- Updating test_thinking_modes.py with proper capabilities mocking in all thinking mode tests
- Updating test_tools.py with proper capabilities mocking for CodeReview and Analyze tools
- Fixing test_large_prompt_handling.py by adding proper provider mocking to prevent errors before large prompt detection

Fixed pytest collection warnings by:
- Renaming TestGenRequest to TestGenerationRequest to avoid pytest collecting it as a test class
- Renaming TestGenTool to TestGenerationTool to avoid pytest collecting it as a test class
- Updated all imports and references across server.py, tools/__init__.py, and test files

All 459 tests now pass without warnings or MagicMock comparison errors.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

tests/test_auto_mode.py

@@ -160,6 +160,7 @@ class TestAutoMode:
                 patch("providers.registry.ModelProviderRegistry.get_provider_for_model") as mock_provider,
                 patch("providers.registry.ModelProviderRegistry.get_available_models") as mock_available,
                 patch.object(tool, "_get_available_models") as mock_tool_available,
+                patch("providers.registry.ModelProviderRegistry.is_model_available") as mock_is_available,
             ):
 
                 # Mock that o3 is not available but actual available models are
@@ -198,6 +199,12 @@ class TestAutoMode:
                 # Mock the tool's available models method to return the actual available models
                 mock_tool_available.return_value = available_models
 
+                # Mock is_model_available to return False for o3 specifically
+                def mock_model_available(model_name):
+                    return model_name != "o3" and model_name in available_models
+
+                mock_is_available.side_effect = mock_model_available
+
                 # Execute with unavailable model
                 result = await tool.execute(
                     {"files": ["/tmp/test.py"], "prompt": "Analyze this", "model": "o3"}  # This model is not available