AppRunner: "Create Service" from ECR node provides default values

When creating an AppRuner service from the ECR node, Toolkit should set default values for:

1. port
- For reference, https://github.com/aws/aws-toolkit-jetbrains defaults to port=80.
2. name
3. compute size (is the current first item the best choice?)


Start from the Create Service action launched from the ECR node and inspect how AppRunner service creation currently chooses port, name, and compute size. Compare the existing behavior with the requested defaults, including port 80, and verify that creating a service from ECR populates all three values appropriately.

Written by the indexing model from the issue text.