resources: Add more details to .Err

This commit adds a .Data object (a map with `Body`, `StatusCode` etc.) to the .Err returned from `resources.GetRemote`, which means you can now do:

```
{{ with .Err }}
{{ range $k, $v := .Data }}
{{ end }}
{{ end }}
```

Fixes #9708

resources/resource.go

@@ -233,7 +233,7 @@ func (l *genericResource) Content() (any, error) {
 	return l.content, nil
 }
 
-func (r *genericResource) Err() error {
+func (r *genericResource) Err() resource.ResourceError {
 	return nil
 }