Journey 5c fails on main since every space got its own main conversation: the lookup picked the Lab conversation instead of the home one. Same change as #126 (including its chart-links warm-up), so this PR can go green; it no-ops once #126 lands. Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01YTJRkJrXAS9e3aEFcFYTy8