Add the stats:stuck-cohort-report command, scheduled weekly, that reports
the percentage of onboarded users stuck at the paywall: users with a
non-deleted banking connection but no valid subscription.
The percentage uses onboarded users (onboarded_at not null) as the
denominator, since that is the population that has reached the paywall.
Each run persists a weekly snapshot (date, onboarded_count, stuck_count,
stuck_pct) and compares against the most recent previous snapshot to
report the week-over-week delta in points and raw stuck count. The first
run reports current figures only.
The Discord payload follows the existing SendAiCohortReportCommand pattern
and posts to the shared services.discord.ai_cohort_webhook_url webhook.
Víctor Falcón