Venture loop: launch products, not pages

Ported from the notplanned venture template:
- launch round: every board seat writes a launch plan (positioning, first
  users, pricing, channels, 7-day success and kill lines); one seat
  synthesizes them into LAUNCH.md with where each idea came from
- launch page brief: one primary call to action in the hero, the working
  product preloaded with a sample, why-this-exists with real star counts,
  pricing (free plus at most two honest early-access tiers), honest limits,
  a design direction that rotates and never repeats the last six
- signups through a GitHub issue form prefilled with venture and plan;
  each signup is thanked on its own issue
- checks: deterministic gates, then headless Chrome measuring at exactly
  390x844 and 1280x800 (horizontal scroll, button below the fold, JS
  errors); two fix rounds, then andon with needs-human and /time retry
- a contact-sheet screenshot of phone and desktop on the card
- 7-day decision on distinct people: v2 card, kill, or one more week then
  park; a next version counts only signups after its own launch
- scheduling: a card that is measuring never blocks the others; one new
  card a day; a tick runs light stages back to back and one worker run
- the studio index at /ventures/ is generated from ventures.json

Security: the worker's shell no longer sees tokens or keys, its checkout
keeps no token in .git/config, and workflows don't persist credentials.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UpT7eWzeLhRwuYmsSQnbRb

.github/workflows/update.yml

@@ -24,7 +24,7 @@ jobs:
       - name: copy engine, open PR if changed
         run: |
           set -e
-          for f in .github/time/time.py .github/time/venture.py .github/time/test_time.py .github/time/seats.json .claude/skills/time/SKILL.md; do
+          for f in .github/time/time.py .github/time/venture.py .github/time/test_time.py .github/time/seats.json .github/ISSUE_TEMPLATE/early-access.yml .claude/skills/time/SKILL.md; do
             mkdir -p "$(dirname "$f")"; cp "/tmp/up/$f" "$f"
           done
           python3 .github/time/test_time.py > /dev/null