Reconciles month-old working-tree UX work (served per-request, live on the demo since
2026-05-30) into git. Implements UX_FIX_PLAN.md's 5 user complaints: reference pages
(Profiler/Architecture/Spec/Onboard/Alerts/Workspaces) open in new tabs; contract-card
collapsible shows a persistent chevron + expand/collapse label in both states; proof.html
gains a substrate-signals chapter. Not authored this session — captured as-is (working
state verified: pages serve 200).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>