FX.117 Accuracy Changes tab: search, filters, and a before/after check on each fix (1,000,000 inputs)

Owner 2026-11-07. /accuracy/changes now has a search box, tag chips and App / What happened / Before and after filters (server-side, 50 a page). Each of the 7 fixes was run before and after on 1,000,000 generated inputs (tools/accuracy-equality/verify.mjs, one recipe per change in checks/): all 7 show 'Corrected' (the old text was wrong on 13 to 45 percent of inputs, the new text on none) and link to /accuracy/changes/EQ-n with counts, samples and the seed; the raw file is /accuracy/changes/EQ-n.json and lives in core/data/equality-results/ so it can be copied to a CDN (.env NUMERICS_RESULTS_CDN makes the links point there). Limits: it runs the changed comparison text with generated inputs, not the whole app; the 'right answer' is within 1e-12 relative, which is my definition; 277 tag-only entries have nothing to compare. Not done: no revert button on the page; app suites not re-run.