fix: add type hints for encoding parameter in parser_tools

[cybs-joe]

Added 'str' type hint to the encoding parameter in from_unicode, to_unicode, and data_encode functions.

Used Claude (claude-sonnet-4-6) to identify untyped parameters and suggest the fix. Reviewed and validated all changes manually.

Refs issue 938

• Refs Add type hints [beginner, Python, typing] #938

Description

Added str type hint to the encoding parameter in from_unicode,
to_unicode, and data_encode in src/icalendar/parser_tools.py.

Checklist

• I've added a change log entry to /news, following the instructions in Change log entry format.
• I've added or updated tests if applicable.
• I've run and ensured all tests pass locally by following Run tests.
• I've added or edited documentation, both as docstrings to be rendered in the API documentation and narrative documentation, as necessary.

Additional information

Upload screenshots, videos, links to documentation, or any other relevant information.

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Documentation build overview

📚 icalendar | 🛠️ Build #32821094 | 📁 Comparing f2e9fa2 against latest (151516a)

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5 files changed · ± 5 modified

± Modified

• 404.html
• _modules/icalendar/parser_tools.html
• reference/api/icalendar.cal.component.html
• reference/api/icalendar.parser_tools.html
• _modules/icalendar/cal/component.html

[stevepiercy]

This is good.

My suggestion adds markup to show that it's an inline literal. With that change, it can be merged.

Thank you!

[stevepiercy]

@cybs-joe would you please edit the description from Closes to Refs? We don't want to close that issue when this PR is merged, as there are many more places to add type hints. Thank you!

[stevepiercy]

Thank you!