Add Python Parser Implementation

[issamelimrany]

Changes Made

• Implemented PythonParser class with support for:
  • Finding enclosing contexts (functions and classes)
  • Validating Python code syntax
  • Error handling for invalid Python code
• Added Python file extension mappings (.py, .python) to the parser registry
• Updated type definitions to support Python AST nodes

Implementation Details
The Python parser:

• Uses python-ast for parsing Python source code
• Identifies function and class definitions as enclosing contexts
• Maintains consistent interface with existing JavaScript parser
• Provides proper error handling and validation