Initial BizOne portal setup

reference/02-system-architecture.md

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+# System Architecture
+
+## Core Components
+
+### Frontend Admin Dashboard
+- Next.js
+- TailwindCSS
+- shadcn/ui
+- TanStack Table
+- Recharts
+
+### Backend API
+- NestJS
+- Prisma ORM
+- PostgreSQL
+
+### Webhook Receiver
+- Public HTTPS endpoint
+- Signature validation
+- Raw payload logging
+- Queue handoff for processing
+
+### Worker / Queue
+- Redis
+- BullMQ
+- Handles bulk send, scheduled send, webhook processing, retries
+
+### Storage
+- S3 compatible or local object storage for media, import/export files
+
+## Logical Flow
+1. Admin uses dashboard
+2. Frontend calls backend API
+3. Backend stores data in PostgreSQL
+4. Bulk and async jobs go to Redis/BullMQ
+5. Worker sends outbound messages to provider
+6. Provider calls webhook endpoint
+7. Webhook receiver stores raw events and dispatches processing jobs
+8. Processed statuses update messages, conversations, and campaign recipients
+
+## Security
+- JWT + refresh token
+- Role-based access control
+- Secret encryption at rest
+- Webhook signature validation
+- Audit logs
+- Rate limiting on public endpoints
+
+## Deployment Recommendation
+- Dockerized services
+- Reverse proxy via Nginx
+- HTTPS domain for webhook
+- Separate worker process