irisandClaude Opus 5
1a9655414e
She asked whether `masked_by` earns its place, since `.background(x).masked()` looks like the same thing. Measured: for a square-cornered surface it is (identical to the pixel on the composer at the phone's size and density), and what the pair cannot express is a clip that is not a box, which is why the method stands for now. Her suggestion, in IRIS_TODO.md's "Reconsider": let `Stack` name where its mask comes from the way `StackSize::Child(n)` already names where its size comes from, at which point `masked_by` and `Masked::shape` both go away. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>