Implement SIMD boolean operations for WASM

[no-materials]

This PR implements the previously TODO-marked SIMD boolean operations for WASM targets.

Changes Made

• The reinterpretation logic for these operations was already implemented in the codebase. This PR removes the special conditions that were preventing these operations from being generated through the normal code flow.

• Implemented tests for each boolean operation, currently covering the i8x16 vector type to verify correctness of the implementation.

Operations Implemented

The following SIMD boolean operations are now available for WASM:

• and, or, xor, not

Testing

Added test coverage for each operation using the i8x16 vector type.

Should I extend the test suite to cover additional vector types, or is the current i8x16 coverage sufficient?

[LaurenzV]

Thanks! Will let @ajakubowicz-canva do the review because he is more familiar with WASM, but it looks good.

Should I extend the test suite to cover additional vector types, or is the current i8x16 coverage sufficient?

I think that's up to you, in the future we will obviously want to have tests for "everything", but we don't really have a proper test suite in place. This will happen eventually, but right now our focus is just to add all operations we need to vello.

[ajakubowicz-canva]

Thank you so much. With the inclusion of those tests I'm very happy with this. I echo @LaurenzV that adding tests across all operators would be ideal, but it can be optional.

Thank you!

Edit: I realized that I am not aware if you're able to merge. Let me know if you need myself or Laurenz to merge this PR.

[no-materials]

Thank you so much. With the inclusion of those tests I'm very happy with this. I echo @LaurenzV that adding tests across all operators would be ideal, but it can be optional.

Thank you!

Edit: I realized that I am not aware if you're able to merge. Let me know if you need myself or Laurenz to merge this PR.

Thank you for the positive feedback! I've added additional tests covering unsigned and mask vector types to provide broader coverage of the boolean operations.
I decided not to extend tests to all vector sizes at this time since, as @LaurenzV mentioned, a proper comprehensive test suite will be implemented in the future.

I don't have merge permissions, so I'd appreciate if you or @LaurenzV could merge this PR when you're ready.

Thanks again for the review and guidance!

[ajakubowicz-canva]

Thank you so much! Changes look great. I'll merge once CI passes.