clippy: fix rust 1.95 lints

[xtqqczze]

Closes #11858
Closes #11859

Unblock CI after toolchain change to Rust 1.95

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/tail/retry. tests/tail/retry is passing on 'main'. Maybe you have to rebase?
Skip an intermittent issue tests/cut/bounded-memory (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/date/resolution (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/date/date-locale-hour (passes in this run but fails in the 'main' branch)
Note: The gnu test tests/csplit/csplit-heap is now being skipped but was previously passing.
Skip an intermittent issue tests/pr/bounded-memory (was skipped on 'main', now failing)

[codspeed-hq]

Merging this PR will degrade performance by 5.34%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 4 improved benchmarks
❌ 6 regressed benchmarks
✅ 299 untouched benchmarks
⏩ 46 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	cksum_sha256	1.7 s	1.8 s	-4.04%
❌	Simulation	cksum_crc32b	13 ms	13.7 ms	-5.34%
❌	Simulation	cksum_sha2	1.7 s	1.8 s	-4.04%
⚡	Simulation	cksum_blake2b	192.7 ms	183.9 ms	+4.8%
❌	Simulation	cksum_sha224	1.7 s	1.8 s	-4.05%
❌	Simulation	nl_many_lines[100000]	18.9 ms	19.6 ms	-3.68%
❌	Simulation	nl_large_file[10]	24.1 ms	25 ms	-3.73%
⚡	Simulation	split_bytes	401.8 µs	389.7 µs	+3.1%
⚡	Simulation	fold_custom_width[50000]	25.3 ms	22.9 ms	+10.22%
⚡	Simulation	fold_many_lines[100000]	63.8 ms	57.3 ms	+11.41%

---

_{Comparing xtqqczze:clippy/rustc195 (8efa060) with main (5b54e08)}

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. ↩

[xtqqczze]

Merging this PR will degrade performance by 5.34%

@oech3 Is it worth investigating Rust 1.95 toolchain CodSpeed regressions?

[oech3]

I think so

[xtqqczze]

I think so

Rust 1.95 upgraded to LLVM 22 (rust-lang/rust#150722), so investigating a ~5% regression is likely too complex for the potential benefit.

[oech3]

Just wait fix at upstream

[xtqqczze]

@sylvestre It would be nice to run a clippy job using beta toolchain to catch list issues early

[cakebaker]

Thanks!