fix: use static manifest file instead of dynamic creation

- Create terraform-registry-manifest.json as a static file in the repo
- Remove echo command from before hooks that was creating it dynamically
- Restore extra_files configuration in checksum section
- This ensures the file exists when GoReleaser looks for it

Author: Trozz

.goreleaser.yml

@@ -11,8 +11,6 @@ before:
     # Generate documentation
     - go install github.com/hashicorp/terraform-plugin-docs/cmd/tfplugindocs@latest
     - tfplugindocs generate
-    # Create Terraform Registry manifest
-    - echo '{"version":1,"metadata":{"protocol_versions":["6.0"]}}' > terraform-registry-manifest.json
 
 # Build configuration
 builds:

terraform-registry-manifest.json

@@ -0,0 +1,6 @@
+{
+  "version": 1,
+  "metadata": {
+    "protocol_versions": ["6.0"]
+  }
+}