push_dabs clamped the number of intermediate dabs of one brush segment to 1,000,000, so a
finite but extreme segment (a point 10,000,000 px away) still allocated a million dabs. A
segment that would need more than that many now keeps only its endpoints; ordinary
spacing and the segment's end point are unchanged.
Adds oversized_brush_segments_skip_intermediate_dabs, which checks both the extreme case
(2 dabs) and an ordinary feathered-brush segment (21 dabs, end point kept, spacing kept).
The docs record the fix under gap 24 and LR-MASK-BRUSH; the parity status stays partial.
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