feat: Full petmaster CRM with NestJS API and React frontend

- Client management (CRUD with JSONB custom fields)
- Pet profiles
- Service catalog with per-client pricing
- Booking calendar with recurring appointments
- Invoicing with Stripe integration
- Real-time messaging (WebSocket)
- Self-booking portal
- Staff assignment
- Docker multi-stage builds
- Prisma schema + seed

web/Dockerfile

@@ -0,0 +1,15 @@
+# Dockerfile for frontend
+FROM node:22-alpine AS builder
+
+WORKDIR /app
+
+COPY package.json yarn.lock* ./
+RUN yarn install --frozen-lockfile 2>/dev/null || npm install
+
+COPY . .
+RUN npm run build
+
+FROM nginx:alpine
+COPY --from=builder /app/build /usr/share/nginx/html
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+EXPOSE 3001