Add strongly typed MCP types: Tool, ToolError, rename types.py to mcp_types.py

[Copilot]

• Rename types.py to mcp_types.py to avoid conflict with Python's types module
• Create strongly typed Tool dataclass with name, description, input_schema, output_schema
• Create typed ToolError class with error_type (enum), message, and details
• Update ListToolsObservation to use typed List[Tool] instead of List[Dict[str, Any]]
• Update CallToolObservation to make fields required and use typed ToolError class
• Update all imports across the codebase that reference types.py
• Update __init__.py to export new types (Tool, ToolError, ToolErrorType)
• Add pytest pythonpath configuration to pyproject.toml
• Run code review and fix feedback
• Run security analysis (CodeQL) - no issues found
• Add comprehensive tests for MCP types (21 tests for Tool, ToolError, observations)
• Fix test directory structure to avoid import conflicts
• All 23 tests pass

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[Darktex]

@copilot add tests to validate that these changes are working as intended. Run the tests and show me

[Copilot]

@copilot add tests to validate that these changes are working as intended. Run the tests and show me

Added comprehensive tests in commit 4843088. Here are the test results:

23 tests passed in 1.12s

Tests added for:
- Tool: creation, serialization, equality
- ToolError: creation, details, serialization  
- ToolErrorType: all enum values, from-string parsing
- ListToolsObservation: empty, with tools, serialization
- CallToolObservation: success, with error, serialization
- Actions: ListToolsAction, CallToolAction
- MCPEnvironment: typed tools, error handling

Run the tests with:

python -c "
import sys
sys.path.insert(0, 'src')
import pytest
pytest.main(['-v', 'tests/core/test_mcp_module/'])
"