Apply hoist optimizations to Geometry.c's transforms

[akx]

Like the other recent optimization PRs: hoist im*->xsize and im*->ysize into locals so autovectorization can do its thing.

[codspeed-hq]

Merging this PR will improve performance by 14.41%

⚠️ 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

⚡ 13 improved benchmarks
✅ 332 untouched benchmarks
⏩ 2 skipped benchmarks¹

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	test_rotate_right[1024x1024-L-ROTATE_180]	4.5 ms	3.6 ms	+24.06%
⚡	test_rotate_right[1024x1024-L-FLIP_LEFT_RIGHT]	4.5 ms	3.6 ms	+24.05%
⚡	test_rotate_right[1024x1024-RGBA-ROTATE_180]	7.4 ms	6.5 ms	+13.44%
⚡	test_rotate_right[1024x1024-LA-ROTATE_180]	7.4 ms	6.5 ms	+13.44%
⚡	test_rotate_right[1024x1024-RGB-ROTATE_180]	7.4 ms	6.5 ms	+13.44%
⚡	test_rotate_right[1024x1024-RGBA-FLIP_LEFT_RIGHT]	7.4 ms	6.5 ms	+13.44%
⚡	test_rotate_right[1024x1024-LA-FLIP_LEFT_RIGHT]	7.4 ms	6.5 ms	+13.43%
⚡	test_rotate_right[1024x1024-RGB-FLIP_LEFT_RIGHT]	7.4 ms	6.5 ms	+13.42%
⚡	test_scale[1024x1024-LA-2.14-NEAREST]	37.5 ms	33.5 ms	+11.96%
⚡	test_scale[1024x1024-RGBA-2.14-NEAREST]	37.5 ms	33.5 ms	+11.91%
⚡	test_scale[1024x1024-F-2.14-NEAREST]	37.5 ms	33.5 ms	+11.91%
⚡	test_scale[1024x1024-I-2.14-NEAREST]	37.5 ms	33.5 ms	+11.9%
⚡	test_scale[1024x1024-RGB-2.14-NEAREST]	37.5 ms	33.5 ms	+11.89%

Tip

Curious why this is faster? Comment @codspeedbot explain why this is faster on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing akx:faster-geometry-1 (ffd82f2) with main (b39b964)}

Footnotes

1. 2 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. ↩