Admin-only Claude (Sonnet 4.6) chat embedded on the dashboard under the
welcome text. Attach received-invoice PDFs → extract (vision + structured
output) → confirm/edit → save via the existing received-invoices endpoint.
$50/month admin-editable budget enforced via an ai_usage table + pre-call
guard. New @anthropic-ai/sdk dep, ANTHROPIC_API_KEY, ai.use permission;
one migration. No system-data tools (Phase 2). Ships as v2.1.0.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>