Collect metric definitions from users

Gather from users: what they look at today, exact definitions, filters. Document mission critical vs nice to have for go-live.

Sources (Mar 2026 planning)

• Mar 16, 2026 CC Dashboard session (Sarah / Chris / Ryan): primary input for metric definitions; detailed recap in internal planning doc docs/CC_Dashboard_Plan_Mar_16_2026.md.
• Mar 17 standup: Engineering approach—Better Auth first, admin subdomain + folder structure, umbrella categories across brands, views/caching for aggregates.