feat: add Drizzle ORM configuration for PostgreSQL integration in backend

backend/drizzle.config.ts

@@ -0,0 +1,19 @@
+import { defineConfig } from 'drizzle-kit';
+import * as process from "node:process";
+
+export default defineConfig({
+  schema: './src/schemas',
+  out: '.migrations',
+  dialect: "postgresql",
+  casing: "snake_case",
+  dbCredentials: {
+    host: String(process.env.POSTGRES_HOST || "localhost"),
+    port: Number(process.env.POSTGRES_PORT || 5432),
+    database: String(process.env.POSTGRES_DB || "app"),
+    user: String(process.env.POSTGRES_USER || "app"),
+    password: String(process.env.POSTGRES_PASSWORD || "app"),
+    ssl: false,
+  },
+  verbose: true,
+  strict: true,
+});