fix: install devDeps for build, relax TS strict

Co-authored-by: Cursor <cursoragent@cursor.com>

render.yaml

@@ -3,7 +3,7 @@ services:
     name: eene-dashboard-backend
     runtime: node
     rootDir: backend
-    buildCommand: npm install && npm run build && npx prisma generate && npx prisma db push
+    buildCommand: npm install --include=dev && npm run build && npx prisma generate && npx prisma db push
     startCommand: npm start
     envVars:
       - key: DATABASE_URL