Define an order for class variables that have annotations

I think we should we define a specific order for class variables with the `@Input()` `@Output()` and `@ViewChild()` annotations.

The issue names Angular class variables using @Input(), @Output(), and @ViewChild(), but it does not identify a file, test, or existing convention entry point. First clarify the intended ordering and where frontend conventions are documented; done means the agreed order is recorded in the relevant convention guidance.

Written by the indexing model from the issue text.