@argument completion with Typescript AddOn in Visual Studio Code

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I have a component I'm developing leveraging ember-cli-typescript and ember-cli-addon-docs using the YUIDoc generator.

I'm following the YUIDoc spec to document my arguments in my interface like this:
```typescript
interface MyComponentArgs extends BaseComponentArgs {
/**
* A Custom CSS class to be added to the base component classes.
* @argument class
* @type {String}
* @public
*/
class: string;
}
```
(open to syntax corrections if there are any)

## My issue:
When in Visual Studio Code, I can type `<` and see the component name autocompletion, but when I go to then type `@` to get access to the autocomplete menu for the arguments of the component, none of the arguments appear.

**Example:** *(while in VSCode)*
```handlebars

Reproduce the missing argument completion in Visual Studio Code using the TypeScript interface and YUIDoc annotations shown in the issue. Start by tracing the Ember Language Server Addon Docs completion provider, and consider the issue done when typing @ after

Written by the indexing model from the issue text.