Get Creator Dashboard

T5-1 (BILLING_RULES.md §13): trial-state info for the dashboard.

status is one of: - None / 'active' (legacy non-trial OR completed-trial creator) - 'trial_awaiting_invoice' (signed up, no advisory yet) - 'trial_card_pending' (advisory issued, 5-day window open) - 'trial_lapsed' (card not added in time; new opts blocked) days_remaining is positive when in trial_card_pending and counts down from 5; null otherwise. terminal_at is set when smart-retry exhausted (T4-7).