Improve documentation for Python modules

[techupskills]

Several Python modules lack sufficient in-code documentation. Improve the docstrings and comments to help future contributors understand the purpose and usage of each module, class, and function.

Tasks:

• Review all .py files for missing or unclear docstrings.
• Add or update docstrings for modules, classes, and functions.
• Ensure documentation follows standard style (e.g., Google, NumPy, or reStructuredText).

Acceptance Criteria:

• All major public functions and classes are documented.
• Docstring format is consistent across the codebase.