Infrastructure: Sync existing staging infrastructure with Terraform Script #1337

Description

Most staging infrastructure (VPC, subnets, security groups, EC2 instances, etc.) was created manually from the AWS console. We need to bring these resources under Terraform by importing them into the staging state, without recreating or changing anything that is running. After this, staging changes should go through Terraform.

Tasks

• List the manually created staging resources (VPC, subnets, route tables, security groups, EC2, ALB, RDS, IAM roles)
• Import them into Terraform and add the matching code to the modules
• Replace hard-coded IDs in tfvars with module outputs where possible
• Add prevent_destroy to critical resources (VPC, RDS, EC2)