Add Terraform AWS infrastructure and enhanced CI/CD pipeline (FRE-4574)

- Terraform modules: VPC, ECS Fargate, RDS PostgreSQL, ElastiCache Redis, S3, Secrets Manager, CloudWatch
- Multi-environment support: staging and production configs
- ECS auto-scaling: CPU-based scaling with configurable min/max
- CI/CD: pnpm caching, Docker Buildx, Trivy security scanning, Terraform plan on PR
- Deploy: ECS service updates with automatic rollback on health check failure
- Backup: automated RDS snapshots, S3 versioning, ElastiCache snapshots
- Monitoring: CloudWatch dashboards, CPU/memory/5xx alarms
- Rollback script for manual service rollback
- Infrastructure documentation with architecture overview

infra/modules/vpc/main.tf

@@ -0,0 +1,235 @@
+variable "environment" {
+  description = "Deployment environment"
+  type        = string
+}
+
+variable "vpc_cidr" {
+  description = "CIDR block for VPC"
+  type        = string
+}
+
+variable "az_count" {
+  description = "Number of availability zones"
+  type        = number
+}
+
+variable "project_name" {
+  description = "Project name"
+  type        = string
+}
+
+resource "aws_vpc" "main" {
+  cidr_block           = var.vpc_cidr
+  enable_dns_support   = true
+  enable_dns_hostnames = true
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-vpc"
+  }
+}
+
+data "aws_availability_zones" "available" {
+  state = "available"
+}
+
+resource "aws_subnet" "public" {
+  count = var.az_count
+
+  vpc_id                  = aws_vpc.main.id
+  cidr_block              = cidrsubnet(var.vpc_cidr, 8, count.index)
+  availability_zone       = data.aws_availability_zones.available.names[count.index]
+  map_public_ip_on_launch = true
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-public-${data.aws_availability_zones.available.names[count.index]}"
+    "kubernetes.io/role/elb" = "1"
+  }
+}
+
+resource "aws_subnet" "private" {
+  count = var.az_count
+
+  vpc_id            = aws_vpc.main.id
+  cidr_block        = cidrsubnet(var.vpc_cidr, 8, var.az_count + count.index)
+  availability_zone = data.aws_availability_zones.available.names[count.index]
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-private-${data.aws_availability_zones.available.names[count.index]}"
+    "kubernetes.io/role/internal-elb" = "1"
+  }
+}
+
+resource "aws_internet_gateway" "main" {
+  vpc_id = aws_vpc.main.id
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-igw"
+  }
+}
+
+resource "aws_eip" "nat" {
+  count = var.az_count
+
+  domain = "vpc"
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-nat-${count.index}"
+  }
+}
+
+resource "aws_nat_gateway" "main" {
+  count = var.az_count
+
+  allocation_id = aws_eip.nat[count.index].id
+  subnet_id     = aws_subnet.public[count.index].id
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-nat-${count.index}"
+  }
+
+  depends_on = [aws_internet_gateway.main]
+}
+
+resource "aws_route_table" "public" {
+  vpc_id = aws_vpc.main.id
+
+  route {
+    cidr_block = "0.0.0.0/0"
+    gateway_id = aws_internet_gateway.main.id
+  }
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-public-rt"
+  }
+}
+
+resource "aws_route_table" "private" {
+  count = var.az_count
+
+  vpc_id = aws_vpc.main.id
+
+  route {
+    cidr_block     = "0.0.0.0/0"
+    nat_gateway_id = aws_nat_gateway.main[count.index].id
+  }
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-private-rt-${count.index}"
+  }
+}
+
+resource "aws_route_table_association" "public" {
+  count = var.az_count
+
+  subnet_id      = aws_subnet.public[count.index].id
+  route_table_id = aws_route_table.public.id
+}
+
+resource "aws_route_table_association" "private" {
+  count = var.az_count
+
+  subnet_id      = aws_subnet.private[count.index].id
+  route_table_id = aws_route_table.private[count.index].id
+}
+
+resource "aws_security_group" "ecs" {
+  name_prefix = "${var.project_name}-${var.environment}-ecs"
+  vpc_id      = aws_vpc.main.id
+
+  ingress {
+    from_port   = 3000
+    to_port     = 3003
+    protocol    = "tcp"
+    cidr_blocks = ["0.0.0.0/0"]
+    description = "Service ports"
+  }
+
+  egress {
+    from_port   = 0
+    to_port     = 0
+    protocol    = "-1"
+    cidr_blocks = ["0.0.0.0/0"]
+  }
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-ecs-sg"
+  }
+}
+
+resource "aws_security_group" "rds" {
+  name_prefix = "${var.project_name}-${var.environment}-rds"
+  vpc_id      = aws_vpc.main.id
+
+  ingress {
+    from_port       = 5432
+    to_port         = 5432
+    protocol        = "tcp"
+    security_groups = [aws_security_group.ecs.id]
+    description     = "PostgreSQL from ECS"
+  }
+
+  egress {
+    from_port   = 0
+    to_port     = 0
+    protocol    = "-1"
+    cidr_blocks = ["0.0.0.0/0"]
+  }
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-rds-sg"
+  }
+}
+
+resource "aws_security_group" "elasticache" {
+  name_prefix = "${var.project_name}-${var.environment}-elasticache"
+  vpc_id      = aws_vpc.main.id
+
+  ingress {
+    from_port       = 6379
+    to_port         = 6379
+    protocol        = "tcp"
+    security_groups = [aws_security_group.ecs.id]
+    description     = "Redis from ECS"
+  }
+
+  egress {
+    from_port   = 0
+    to_port     = 0
+    protocol    = "-1"
+    cidr_blocks = ["0.0.0.0/0"]
+  }
+
+  tags = {
+    Name = "${var.project_name}-${var.environment}-elasticache-sg"
+  }
+}
+
+output "vpc_id" {
+  description = "VPC ID"
+  value       = aws_vpc.main.id
+}
+
+output "private_subnet_ids" {
+  description = "Private subnet IDs"
+  value       = aws_subnet.private[*].id
+}
+
+output "public_subnet_ids" {
+  description = "Public subnet IDs"
+  value       = aws_subnet.public[*].id
+}
+
+output "ecs_security_group_id" {
+  description = "ECS security group ID"
+  value       = aws_security_group.ecs.id
+}
+
+output "rds_security_group_id" {
+  description = "RDS security group ID"
+  value       = aws_security_group.rds.id
+}
+
+output "elasticache_security_group_id" {
+  description = "ElastiCache security group ID"
+  value       = aws_security_group.elasticache.id
+}