refactor: modernize python samples and integrate ruff linter

[0x8000-0000]

• Integrate ruff as the primary linter and formatter in pyproject.toml.
• Replace os.path usage with pathlib.Path for improved path handling.
• Update type annotations to use modern syntax (e.g., str | None instead of Optional[str]).
• Use Annotated for FastAPI dependencies to improve readability and tool support.
• Standardize code formatting across all Python sample files using a 2-space indentation.
• Add missing docstrings and __init__.py files to improve package structure and documentation.
• Address various linting warnings and modernize import statements.

[0x8000-0000]

More details regarding fixed comprehensive linting warnings:

• Wrapped long lines to comply with the 80-character limit.
• Updated docstrings to use the imperative mood.
• Added missing docstrings for classes, packages, and init methods.
• Replaced 'os.path' usage with 'pathlib.Path' for modern path management.
• Migrated FastAPI dependencies to use 'Annotated' for better type safety and linting.
• Removed unused imports and simplified boolean logic.