Enable RUF and PT ruff rules

[NMertsch]

Enable the RUF and PT ruff rule sets and handle all findings.

These changes were not requested. If you don't want them, please just reject the PR. If you want only a subset, or all changes spread over multiple PRs, please let me know.

Here are all code changes:

RUF - ruff-specific rules

• 1595e70: RUF001 - Label ambiguous non-ASCII characters in code
• d35c8b3: RUF003 - Normalize or label ambiguous non-ASCII characters in comments
• 88afbc9: RUF005 - Replace collection concatenations with unpacking
• fad6a61: RUF012 - Annotate mutable class attributes as immutable (e.g. dict as Mapping)
• ec3a2d6: RUF013 - Replace x: str = None with x: str | None = None
• 90c6c33: RUF015 - Replace list(...)[0] with iter(next(...))
• 2b890ea: RUF019 - Simplify "dict key is missing or empty" checks
• 08f6b7c: RUF043 - Escape . in Regex patterns
• 5aacfa8: RUF059 - Prefix unused unpacked variables with underscores
• d7ff87f: RUF100 - Remove two unused noqa directives

PT - flake8-pytest-style

• 296fa2a: PT001 - Remove empty parentheses on pytest.fixture calls
• 29da6fc: PT006 - Use tuple instead of str for pytest.mark.parametrize parameter list
• a7add3a: PT007 - Use list instead of tuple for pytest.mark.parametrize cases
• e1661bd: PT011 - Check for error messages in pytest.raises()
• 563d61c: PT012 - Simplify pytest.raises() blocks
• 574a4fb: PT014 - Remove duplicate test cases in pytest.mark.parametrize
• 1479207: PT018 - Split assert ... and ... statements
• be79a8c: PT022 - Replace yield in pytest fixture without teardown with return

PR Checklist:

• All new features have been tested
• All new features have been documented
• I have read the CONTRIBUTING.md file
• I will abide by the code of conduct

[freakboy3742]

This looks good; however, I'd argue against adding the RSE ruleset. I understand the braces are redundant, but I think the bracket less syntax is confusing unless you fully understand the underlying behavior, as it means the raise doesn't explicitly read as an empty instantiation.

As a general rule, multiple smaller PRs are preferable to one big one; but in this case, just dropping the RSE rule (and related changes) is fine (unless undoing the RSE changes is easier to do in new PRs).

[NMertsch]

in this case, just dropping the RSE rule (and related changes) is fine

Done.

Resolved