88987f508c
- chroma.detect_background_color had no callers anywhere (auto-detection goes through estimate_background_model / _background_border_cluster). - ForegroundEstimate.background and .correction were computed on every image but never consumed; only .rgb was used. estimate_foreground_rgb now returns the foreground array directly and the dataclass is gone, which also drops pymatting return_background work and a per-image correction-norm pass. Verified: CLI output on samples/TestImage3.png is byte-identical (SHA256) to the pre-cleanup baseline. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>