refactor(lint): improve selected Slither-parity lints

[figtracer]

Project / source scope	Selected detector counts (Foundry/Slither)	Foundry selected detectors	Slither selected detectors (warm build-info)	Foundry vs warm Slither	Slither selected detectors (normal)	Foundry vs normal Slither
solady src	pragma 1/1 too-many-digits 118/116 incorrect-shift 76/51 divide-before-multiply 43/63 unused-return 0/1 timestamp 0/0	105.9 ms ± 0.1 ms	7953.3 ms ± 92.6 ms	75.1× faster	9249.7 ms ± 63.6 ms	87.3× faster
tempo forge-std src	pragma 1/1 too-many-digits 1/1 incorrect-shift 1/1 divide-before-multiply 0/0 unused-return 3/6 timestamp 0/0	107.9 ms ± 1.2 ms	5225.8 ms ± 72.9 ms	48.4× faster	6640.3 ms ± 112.4 ms	61.5× faster
optimism vendored solady src	pragma 0/0 too-many-digits 47/46 incorrect-shift 23/18 divide-before-multiply 20/33 unused-return 0/0 timestamp 0/0	50.1 ms ± 0.3 ms	3066.8 ms ± 14.1 ms	61.2× faster	3750.4 ms ± 32.8 ms	74.9× faster
lib-keccak vendored solady src	pragma 0/0 too-many-digits 50/49 incorrect-shift 23/18 divide-before-multiply 20/33 unused-return 0/0 timestamp 0/0	51.3 ms ± 0.5 ms	3145.6 ms ± 81.3 ms	61.3× faster	3897.4 ms ± 84.9 ms	76.0× faster
openzeppelin v5 contracts	pragma 1/0 too-many-digits 3/3 incorrect-shift 0/0 divide-before-multiply 1/9 unused-return 4/20 timestamp 11/19	78.0 ms ± 0.7 ms	5796.0 ms ± 26.5 ms	74.3× faster	7005.9 ms ± 20.0 ms	89.8× faster

[grandizzy]

lgtm!