SOS RoadSync Production Proxy

Endpoints:

• GET /api/roadsync/health
• GET /api/roadsync/context
• POST /api/roadsync/invoice/create
• POST /api/roadsync/invoice/send-link body: {invoiceId, email?, phone?}
• POST /api/roadsync/invoice/void body: {invoiceId, reason?}
• GET /api/roadsync/invoice/status?invoiceId=...