Adopt the service branch's refactors verbatim so the two branches stop
drifting on these files:
- pipeline.py: split _run_image into _process_rgb + MattingResult (an
in-memory API, exposed as MattingPipeline.run_rgb) and allow injecting
pre-loaded models into MattingPipeline. Disk I/O and debug dumps stay
in _run_image; the algorithm is line-for-line the same.
- foreground.py: estimate_foreground_rgb returns the foreground array
directly; the ForegroundEstimate dataclass carried background/
correction fields nothing consumed.
Verified: default TestImage3 run byte-identical to pre-backport master,
all debug artifacts written, run_rgb output matches run_image bytes
under save_rgba's quantization; both files now diff-clean against
server-edition.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
lhk229
e234a1a13d