Additive release of Stage 6. The CHANGELOG gains a 0.4.3 section above 0.4.2; the
version changes in Cargo.toml and in the version line of the six lockfiles that
resolve wai-quantum. The quantum-wasip2 job requires each new fabric test by name.
The place_for test now also drops the CPU's prediction, so a missing prediction
read as zero would place the CPU where place places the GPU, and fail.
Co-Authored-By: Claude Opus 5.5 <[email protected]>