Refactor Dockerfile and schema.prisma for improved migration handling: Remove migration checks during build, enhance entrypoint script to validate DATABASE_URL and schema.prisma presence, and update schema.prisma to use environment variable for database URL.

prisma/schema.prisma

@@ -5,6 +5,7 @@ generator client {
 
 datasource db {
   provider = "postgresql"
+  url      = env("DATABASE_URL")
 }
 
 model User {