Fix progressive AC refinement JPEG decoding#565
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Progressive AC refinement scans were skipping the last coefficient during EOB-run handling, which left the bitstream misaligned and caused later Huffman decode failures on valid JPEGs. Add the chair_normal regression image to keep this case covered. Made-with: Cursor
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spectralEndinstead of stopping one coefficient earlyspectralStart > spectralEndtests/fileformats/jpeg/masters/chair_normal.jpgas a regression case in the JPEG suitePixie was skipping the last coefficient during progressive AC refinement when
eobRunwas active. That left one refinement bit unread, desynchronized the entropy bitstream, and caused a later Huffman decode to fail even though the JPEG itself was valid.