refactor: use proc macro for wasi ignore reasons

[eduardomourar]

Centralizes the ~400 #[cfg_attr(wasi_runner, ignore = "...")] annotations across the integration tests behind #[uutests::wasi_ignore(ReasonKey)], a proc-macro attribute defined in a new tests/uutests_procs crate.

Context: As per PR 14884 and PR 13687 flagged wasi_runner as a noisy, ad hoc cfg. It can't be replaced with target_os, since the tests always compile for the host (WASI can't spawn the child process they launch) — wasi_runner is the only signal a run is driving a wasm32-wasip1/wasm32-wasip2 binary via wasmtime. This doesn't remove the cfg, just the string-literal duplication around it: every reason is now defined once, alphabetically, in tests/uutests_procs/src/lib.rs 42 keys, down from an initial 57 after merging duplicates), including several that previously had no explanation at all.

#[uutests::wasi_ignore(Reason)] can also be applied to a mod { ... } block instead of one #[test] fn at a time; it recurses into nested modules and attaches the reason to every test inside. tee's linux_only module (21 tests) and truncate's fifo module (3 tests) use this instead of repeating the same key on every test.

Not touched: structural gates that aren't ignore-reasons (feat_diagnostics module gating, #[cfg(wasi_runner)] branches selecting alternate passing assertions).

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/id/setgid. tests/id/setgid is passing on 'main'. Maybe you have to rebase?

[codspeed]

Merging this PR will degrade performance by 5.08%

⚡ 5 improved benchmarks
❌ 3 regressed benchmarks
✅ 391 untouched benchmarks
⏩ 54 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	three_39_bit_primes	371.3 ms	801.5 ms	-53.67%
❌	Simulation	thirteen_39_bit_primes	9 s	9.5 s	-5.37%
❌	Simulation	five_38_bit_primes	1.7 s	1.8 s	-4.97%
⚡	Simulation	false_consecutive_calls	350.2 ns	294.7 ns	+18.85%
⚡	Simulation	tsort_complex_dag[50000]	97.2 ms	87.6 ms	+10.86%
⚡	Simulation	tsort_tree_dag[(10, 3)]	39.4 ms	36.5 ms	+7.92%
⚡	Simulation	tsort_wide_dag[100000]	167 ms	157.6 ms	+5.98%
⚡	Simulation	tsort_linear_chain[1000000]	2 s	1.9 s	+4.99%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing eduardomourar:refactor/wasi-ignore-reasons (7fc1254) with main (8cf2e4f)}

Footnotes

1. 54 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. ↩