Add LastWriteTimeUtc property to ChainablePath

[Copilot]

• Add LastWriteTimeUtc property to ChainablePath struct that returns the last write time in UTC
• Add unit tests for the new property
• Update API verification files
• Build and test changes
• Update README to document the new property

Original prompt

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This section details on the original issue you should resolve

<issue_title>Add LastWriteTimeInUtc</issue_title>
<issue_description></issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #69

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[github-actions]

Test Results

87 tests  +3   87 ✅ +3   0s ⏱️ -1s
 3 suites ±0    0 💤 ±0 
 3 files   ±0    0 ❌ ±0 

Results for commit 0321cc0. ± Comparison against base commit d291085.

♻️ This comment has been updated with latest results.

[coveralls]

Pull Request Test Coverage Report for Build 18431424721

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 9 of 9 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.2%) to 96.525%

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Totals
Change from base Build 18431375497:	0.2%
Covered Lines:	181
Relevant Lines:	189

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💛 - Coveralls

[dennisdoomen]

@copilot also update the readme to mention this new property

[Copilot]

@copilot also update the readme to mention this new property

Updated the README to include LastWriteTimeUtc in the "Working with paths" section (commit 0f3c4ba).