- Rename RenderOpts::scene_output to skip_hdr_step (Pipe::without_hdr_step):
the consumer decodes with Pipe::output_linear or applies the step itself.
- Alpha-only EXRs hold the alpha as it is in every output space (it is
coverage, not encoded colour; it used to be sRGB-decoded).
- Tests: a half-opacity layer over a coloured background (premultiplied and
RGB-over-background paths, golden hashes taken before the change), Rec.
2100 PQ and HLG EXR outputs, raw alpha, and a visible skip of the GPU test
without an adapter.
- docs/architecture.md: the Working Gamma curve for unmanaged projects, and
no HDR step for unmanaged projects or PQ / HLG outputs.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>