Briefs the next brainstorming session with: what we built, the four
contenteditable failure modes that made it unshippable, what's still
in the repo (Playwright harness, dev-server, original spec/plan as
historical reference), the decision pending (CodeMirror 6 vs
textarea-overlay), inputs to load, and an explicit "don't restart
this cycle" caveat against trying a third contenteditable variant.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
