Single source of truth for every open issue across the codebase. Pulls
from LAUNCH_READINESS.md (post-launch sections), TODO.md (deferred
features + simplify follow-ups + wave-Slack pilot), and a fresh sweep
of in-code TODO/FIXME comments.
LAUNCH_READINESS.md now keeps only the pre-cutover deploy checklist and
points to BACKLOG.md for everything else. Cutover note corrected — it
has not happened yet.
Force-added BACKLOG.md despite the /docs/ gitignore rule because
LAUNCH_READINESS.md is tracked and now references it.
