The fold test's float arm no longer re-spells the octave coordinate (OneOctave): each octave's float value is the difference of span_fbm / span_ridged at o + 1 and o octaves, with a stated bound on what the accumulating float sum loses.
New fixed span at halfLength 6 pins the Gl reach operator (nu / halfLength fails); a near-zero midpoint on a stationary path (halfLength 0, and halfLength 1 under a loose speed bound) pins the halfLength-0 fold rule and S_o's reach term.
Builds: yes (to be confirmed by the Yggdrasil job).
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>