build: add Docker entrypoint scripts for automated setup

- Add backend entrypoint with automated Prisma migrations and client regeneration
- Add frontend entrypoint with dependency management
- Update Dockerfiles to use entrypoint scripts
- Ensures database schema stays in sync with Prisma Client after migrations

backend/Dockerfile

@@ -15,8 +15,15 @@ RUN npm install
 # Copy application files
 COPY . .
 
+# Copy and set permissions for entrypoint script
+COPY docker-entrypoint.sh /usr/local/bin/
+RUN chmod +x /usr/local/bin/docker-entrypoint.sh
+
 # Expose port
 EXPOSE 3000
 
-# Start application
+# Set entrypoint
+ENTRYPOINT ["docker-entrypoint.sh"]
+
+# Default command (can be overridden)
 CMD ["npm", "run", "dev"]