v3.8.86

Commits since CHANGELOG generation

d88d460 chore(release): bump version to 3.8.86
e19ef02 chore: mark t2451 complete (pr:#20202 completed:2026-04-20) [skip ci]
7febb3e t2451: close trust-gate loop + preserve PR assignee on CLAIM_RELEASED (#20202)
280763c chore: update simplification state registry
33aa24d GH#20145: gh-audit-log-helper.sh + wrapper integration + anomaly scanner (v2) (#20193)
e3cdfb0 fix(claim-task-id): use git -c flags for http timeouts instead of ineffective env vars (#20196)
b13d193 fix(pre-push-hooks): use ref local SHA and dynamic default branch in privacy guard; expose git push stderr (#20189)
5333bb9 chore: update simplification state registry
e1d2593 docs(vector-search): fix sub-query count and Muvera storage cost inconsistency (GH#20175) (#20186)
770f141 fix(brief): replace head-1-devnull with jq-any single-pass in t2449 NMR detection snippet (#20187)