Client + staff dashboards (unified action inbox / triage surface)

SHIPPED 2026-06-26 (b1ea814): the client dashboard aggregates all 8 work signals — a unified, urgency-sorted action-item inbox (tasks, document requests, forms, signatures, invoices) plus upcoming appointments and an unread bar (messages + notifications). The staff dashboard is a real triage surface: 7 module stat tiles, a Needs-attention section (overdue tasks + pending signatures), and recent activity. Degrades gracefully — a broken module adapter shows 0, never a blank page. 11 unit tests + dashboards E2E.