Add CloudFormation solution tag stack for Terraform infra

Add an empty CloudFormation stack to carry the AWS solution tag,
mirroring the CDK FastMainStack description. Also bump Terraform
version to 0.4.0-tf.1 and update version bump playbooks accordingly.

Author: kunanit

docs/VERSION_BUMP_PLAYBOOK.md

@@ -9,8 +9,9 @@ This document provides a checklist for bumping the version of FAST (Fullstack Ag
 3. **`frontend/package.json`** - Frontend package version (`"version": "X.Y.Z"`)
 4. **`infra-cdk/package.json`** - CDK package version (`"version": "X.Y.Z"`)
 5. **`infra-cdk/lib/fast-main-stack.ts`** - Stack description (`(vX.Y.Z)`)
-6. **`infra-terraform/VERSION`** - Terraform compatibility version (only update if TF is verified compatible with the new FAST version; see `infra-terraform/TF_VERSION_BUMP_PLAYBOOK.md`)
-7. **`CHANGELOG.md`** - Add new version entry at top
+6. **`infra-terraform/VERSION`** - Terraform compatibility version (`X.X.X-tf.X`)(only update if TF is verified compatible with the new FAST version; see `infra-terraform/TF_VERSION_BUMP_PLAYBOOK.md`)
+7. **`infra-terraform/main.tf`** - Stack description (`(vX.X.X-tf.X)`) (only update if TF is verified compatible with the new FAST version; see `infra-terraform/TF_VERSION_BUMP_PLAYBOOK.md`)
+8. **`CHANGELOG.md`** - Add new version entry at top
 
 ## Auto-Generated Files (DO NOT manually update)
 

infra-terraform/TF_VERSION_BUMP_PLAYBOOK.md

@@ -56,8 +56,9 @@ Example:
 ## Procedure
 
 1. Update `infra-terraform/VERSION` with the new version
-2. Update `CHANGELOG.md` with `[Terraform]` labeled entries
-3. Commit, tag with `v<VERSION>`, and push
+2. Update `infra-terraform/main.tf` with the new version in the Cloudformation stack description
+3. Update `CHANGELOG.md` with `[Terraform]` labeled entries
+4. Commit, tag with `v<VERSION-tf.X>`, and push
 
 ```bash
 git tag v$(cat infra-terraform/VERSION)

infra-terraform/VERSION

@@ -1 +1 @@
-0.4.0-tf.0
+0.4.0-tf.1

infra-terraform/main.tf

@@ -97,3 +97,23 @@ module "backend" {
 
   depends_on = [module.cognito, module.amplify_hosting]
 }
+
+# =============================================================================
+# Solution Tag (CloudFormation)
+# =============================================================================
+# Empty CloudFormation stack for AWS solution tag indicator.
+# Maps to: CDK FastMainStack description
+
+resource "aws_cloudformation_stack" "solution_tag" {
+  name = "${var.stack_name_base}-solution-tag"
+
+  template_body = jsonencode({
+    AWSTemplateFormatVersion = "2010-09-09"
+    Description              = "Fullstack AgentCore Solution Template (v0.4.0-tf.1) (uksb-v6dos0t5g8) (tag: terraform)"
+    Resources = {
+      NullResource = {
+        Type = "AWS::CloudFormation::WaitConditionHandle"
+      }
+    }
+  })
+}