docs: clarify Journal.new() and Available.new() docstrings

[checkzhao8888]

Linked issue

• See Clarify auto-generated properties for new class methods #1473

Description

Clarifies the Journal.new() and Available.new() docstrings to align with RFC terminology and match the style used in other new() docstring updates (for example, #1504–#1506).

Changes:

• Replace misleading "with all required properties" summaries.
• Mark optional parameters explicitly.
• Document auto-generated UID and DTSTAMP values when arguments are None.
• Remove a nonexistent end parameter from the Journal.new() docstring.

AI disclosure: Grok assisted with reviewing the implementations, comparing existing new() docstring patterns, and drafting the updates.

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.

[github-actions]

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[read-the-docs-community]

Documentation build overview

📚 icalendar | 🛠️ Build #33302195 | 📁 Comparing da737a8 against latest (937f6fc)

  🔍 Preview build  

5 files changed · ± 5 modified

± Modified

• 404.html
• reference/api/icalendar.cal.available.html
• reference/api/icalendar.cal.journal.html
• _modules/icalendar/cal/available.html
• _modules/icalendar/cal/journal.html

[niccokunzmann]

Complete one PR. Then open the next one when you have engaged in feedback. Closing this as spam for now.
Focus on your open PR and do not be proud to think that either the AI or you have understood what the issue is about.

#1504