bench(sort): add general numeric benchmark

[mattsu2020]

Summary

• Add a benchmark for sort -g (general numeric sort) using decimal and exponent notation data.
• Focus on performance coverage for mixed numeric formats.

related

#9839

[github-actions]

GNU testsuite comparison:

Congrats! The gnu test tests/sort/sort-stale-thread-mem is no longer failing!
Congrats! The gnu test tests/tail/follow-name is no longer failing!
Congrats! The gnu test tests/tty/tty-eof is no longer failing!

[codspeed-hq]

Merging this PR will degrade performance by 13.06%

Summary

❌ 1 regressed benchmark
✅ 138 untouched benchmarks
🆕 1 new benchmark
⏩ 37 skipped benchmarks¹

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

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
❌	sort_long_line[160000]	1.7 ms	1.9 ms	-13.06%
🆕	sort_general_numeric[200000]	N/A	724.1 ms	N/A

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_{Comparing mattsu2020:bench-sort-general-numeric (4ca2965) with main (baf18ab)}

Footnotes

1. 37 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. ↩

[github-actions]

GNU testsuite comparison:

Congrats! The gnu test tests/sort/sort-stale-thread-mem is no longer failing!
Congrats! The gnu test tests/tty/tty-eof is no longer failing!