fix(wasi): touch timestamp handling

[eduardomourar]

touch avoids the filetime crate's panicking WASI fallback by reading timestamps via Metadata::accessed/modified, and uses rustix::fs::utimensat for symlink timestamps since filetime::set_symlink_file_times always fails on WASI.

[github-actions]

GNU testsuite comparison:

Note: The gnu test tests/misc/write-errors was skipped on 'main' but is now failing.
Skip an intermittent issue tests/cut/bounded-memory (was skipped on 'main', now failing)

[codspeed-hq]

Merging this PR will improve performance by 3.03%

⚡ 1 improved benchmark
✅ 344 untouched benchmarks
⏩ 46 skipped benchmarks¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	cksum_crc32b	40.9 ms	39.7 ms	+3.03%

Tip

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_{Comparing eduardomourar:wasi-touch-fixes (0ef5ed9) with main (66e0d60)}

Footnotes

1. 46 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[sylvestre]

This is a lot of cfg. Would it be possible to refactor this a bit? Thanks

[eduardomourar]

I tried simplifying a bit. I believe that the readability would really improve if we moved the wasi (or redox) cfg path to a separate file. The downside is that it will have duplicated code.

[sylvestre]

Please fix the lint