[Lens-lzy]

The Crop tool currently offers only fixed aspect ratios. This adds a 9:20 preset and a Custom… entry that opens a small width:height editor, accepting positive numbers including decimals. Confirming a value displays it in the ratio menu and reshapes the crop frame; dismissing the editor leaves the current ratio unchanged.

For example, choosing 2.5:1 on a 900 × 600 canvas gives a 900 × 360 crop frame. Invalid, non-finite, zero, negative, and unrepresentable ratios cannot be applied. Extreme valid ratios resize within the existing whole-pixel document limits. Free, Original, and the existing presets remain available.

Closes #165.

Validation:

• Built and tested with Xcode 26.2 on Apple silicon, macOS 27.2.
• All 541 CompositorTests passed: 534 in the main run and 7 window tests run separately, following the CI split.
• CropTests: all 9 tests passed, including two new tests in the existing file for input validation, frame sizing, extreme ratios, and existing choices.
• Verified in the running app: the Custom… popover opens with editable text; 0:20 disables Apply; 2.5:1 produces 900 × 360; the 9:20 preset produces 900 × 2000.

[Lens-lzy]

Hi @robbietilton — just a gentle bump on this one. It's been about a week with CI green; happy to adjust anything if you have feedback. Thanks!

[robbietilton]

Merged, thank you @Lens-lzy! Custom… is a great fit: one menu entry covers 4:5, 3:2, 2.35:1 and anything else people need, and the validation and tests were thorough.

A few small changes before merging, to keep the menu short:

• 9:20 is gone as a preset, since Custom… covers it. In its place is 2.39:1, the widescreen cinema ratio.
• The ratios are grouped by shape with dividers: Free and Canvas, then square, then wide (4:3, 16:9, 2.39:1), then tall (3:4, 9:16), then Custom….
• "Original" is now called "Canvas", which says more plainly whose proportions it keeps.