Improve date handling in UniFi Protect media source

[RaHehl]

Breaking change

Proposed change

• Replace manual month increment logic with calendar.monthrange()
• Simplify _format_duration() using divmod pattern
• Normalize _get_month_start_end() to use second=0
• Fix month iteration to use >= instead of > for same-month handling
• Add comprehensive tests for date calculations across all month types

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes Unify Protect - Media Folder December error #159475
• This PR is related to issue:
• Link to documentation pull request:
• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

• I understand the code I am submitting and can explain how it works.
• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• I have followed the perfect PR recommendations
• The code has been formatted using Ruff (ruff format homeassistant tests)
• Tests have been added to verify that the new code works.
• Any generated code has been carefully reviewed for correctness and compliance with project standards.

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• Documentation added/updated for www.home-assistant.io

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  Updated by running python3 -m script.gen_requirements_all.
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To help with the load of incoming pull requests:

• I have reviewed two other open pull requests in this repository.

[Copilot]

Pull request overview

This PR improves date handling in the UniFi Protect media source component by refactoring manual date arithmetic with cleaner, more maintainable approaches using Python's standard library functions.

Key Changes:

• Replaces error-prone manual month increment logic with calendar.monthrange() for accurate month boundary calculations
• Refactors _format_duration() to use the divmod pattern for cleaner time component extraction
• Fixes month iteration logic to correctly handle same-month scenarios by changing comparison from > to >=

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
homeassistant/components/unifiprotect/media_source.py	Implements date calculation improvements: adds monthrange import, simplifies _format_duration() with divmod, normalizes _get_month_start_end() to use second=0, fixes month end calculation in _build_month() and _build_days() using monthrange, and corrects same-month iteration logic
tests/components/unifiprotect/test_media_source.py	Adds comprehensive parameterized test for date calculations covering various month types including leap years and December edge case, but contains a critical bug in the test implementation

[home-assistant]

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