Migrate billing backend from Django to Express + Apollo Server + Prisma

Replace Python/Django/Graphene with TypeScript/Express/Apollo Server.
Same 2 endpoints (team/m2m), same JWT auth, same TigerBeetle integration.
Prisma ORM replaces Django ORM for Account/OperationCode/ServiceAccount.

src/index.ts

@@ -0,0 +1,64 @@
+import express from 'express'
+import cors from 'cors'
+import { ApolloServer } from '@apollo/server'
+import { expressMiddleware } from '@apollo/server/express4'
+import * as Sentry from '@sentry/node'
+import { teamTypeDefs, teamResolvers } from './schemas/team.js'
+import { m2mTypeDefs, m2mResolvers } from './schemas/m2m.js'
+import { m2mContext, teamContext, type AuthContext } from './auth.js'
+
+const PORT = parseInt(process.env.PORT || '8000', 10)
+const SENTRY_DSN = process.env.SENTRY_DSN || ''
+
+if (SENTRY_DSN) {
+  Sentry.init({
+    dsn: SENTRY_DSN,
+    tracesSampleRate: 0.01,
+    release: process.env.RELEASE_VERSION || '1.0.0',
+    environment: process.env.ENVIRONMENT || 'production',
+  })
+}
+
+const app = express()
+
+app.use(cors({ origin: ['https://optovia.ru'], credentials: true }))
+
+const teamServer = new ApolloServer<AuthContext>({
+  typeDefs: teamTypeDefs,
+  resolvers: teamResolvers,
+  introspection: true,
+})
+
+const m2mServer = new ApolloServer<AuthContext>({
+  typeDefs: m2mTypeDefs,
+  resolvers: m2mResolvers,
+  introspection: true,
+})
+
+await Promise.all([teamServer.start(), m2mServer.start()])
+
+app.use(
+  '/graphql/team',
+  express.json(),
+  expressMiddleware(teamServer, {
+    context: async ({ req }) => teamContext(req as unknown as import('express').Request),
+  }) as unknown as express.RequestHandler,
+)
+
+app.use(
+  '/graphql/m2m',
+  express.json(),
+  expressMiddleware(m2mServer, {
+    context: async () => m2mContext(),
+  }) as unknown as express.RequestHandler,
+)
+
+app.get('/health', (_, res) => {
+  res.json({ status: 'ok' })
+})
+
+app.listen(PORT, '0.0.0.0', () => {
+  console.log(`Billing server ready on port ${PORT}`)
+  console.log(`  /graphql/team  - team access token auth`)
+  console.log(`  /graphql/m2m   - internal services (no auth)`)
+})