feat(WHE-27): add drizzle db package and typed env config

packages/db/drizzle.config.ts

@@ -0,0 +1,14 @@
+import { defineConfig } from 'drizzle-kit'
+
+const dbCredentials = process.env.DATABASE_URL
+  ? {
+      url: process.env.DATABASE_URL
+    }
+  : undefined
+
+export default defineConfig({
+  dialect: 'postgresql',
+  schema: './packages/db/src/schema.ts',
+  out: './packages/db/drizzle',
+  dbCredentials
+})