fix: improve env onboarding and dev error messages

.env.example

@@ -0,0 +1,3 @@
+ADMIN_DOMAIN = http://localhost:9001
+DATABASE_URL = postgresql://postgres:postgres@localhost:5432/nextplacement
+AUTH_SECRET= change_me_to_a_long_random_string

apps/student/next.config.mjs

@@ -2,6 +2,7 @@
 import path from 'path';
 
 const __dirname = path.resolve();
+const adminDomain = process.env.ADMIN_DOMAIN || "http://localhost:9001";
 
 const nextConfig = {
   transpilePackages: ['@workspace/ui', '@workspace/db'],
@@ -11,15 +12,15 @@ const nextConfig = {
     return [
         {
             source: '/admin',
-            destination: `${process.env.ADMIN_DOMAIN}/admin`,
+            destination: `${adminDomain}/admin`,
         },
         {
             source: '/admin/:path+',
-            destination: `${process.env.ADMIN_DOMAIN}/admin/:path+`,
+            destination: `${adminDomain}/admin/:path+`,
         },
         {
             source: '/admin-static/:path+',
-            destination: `${process.env.ADMIN_DOMAIN}/admin-static/:path+`,
+            destination: `${adminDomain}/admin-static/:path+`,
         }
     ];
 }

packages/db/index.ts

@@ -1,6 +1,12 @@
 import { drizzle } from 'drizzle-orm/neon-http';
 import * as schema from './schema.ts';
 
-export const db = drizzle(process.env.DATABASE_URL!, { schema });
+const databaseUrl = process.env.DATABSE_URL;
 
-export * from './schema.ts';
+if(!databaseUrl) {
+    throw new Error{
+        "DTABASE_URL is missing. Create the required env file (see .env.example) and set DATABASE_URL"
+    };
+}
+
+export const db = drizzle(databaseUrl, { schema });