Refactor code style and improve documentation

- Standardized string quotes to single quotes across all files.
- Added docstrings to several functions and classes for better clarity.
- Updated mypy configuration in pyproject.toml for enhanced type checking.
- Ignored specific linting rules for test files in ruff configuration.
- Improved error messages in exception handling for better user feedback.
- Cleaned up code formatting and structure for consistency.

pyproject.toml

@@ -47,6 +47,9 @@ indent-style = "space"
 select = ["E", "F", "I", "UP", "B", "Q", "ERA", "D", "SIM", "ARG", "RUF", "C4", "RET", "ASYNC", "PERF", "PL"]
 ignore = ["D100", "RUF002", "D107", "RUF001", "D104", "D203", "D213", "ARG001"]
 
+[tool.ruff.lint.per-file-ignores]
+"tests/**/*.py" = ["D"]
+
 [tool.ruff.lint.flake8-quotes]
 inline-quotes = "single"
 multiline-quotes = "double"
@@ -55,11 +58,16 @@ avoid-escape = true
 
 
 [tool.mypy]
-python_version = "3.13"
+python_version = "3.12"
 strict = true
 warn_unused_ignores = true
 warn_redundant_casts = true
 warn_unreachable = true
+show_error_codes = true
+pretty = true
+explicit_package_bases = true
+files = ["src", "tests", "main.py"]
+mypy_path = "$MYPY_CONFIG_FILE_DIR/src:$MYPY_CONFIG_FILE_DIR/stubs"
 
 [tool.deptry.package_module_name_map]
 "yt-dlp" = "yt_dlp"