`targetScope` does not show up in the document outline view

**Bicep version**
Any

**Describe the bug**
`targetScope` is an element of the document that should be present in the outline.

**To Reproduce**
```bicep
targetScope = 'managementGroup'
param test string
```

The above produces this document outline in VS code:

**Additional context**
The bug exists because we use symbols to populate the response in the document symbols handler.

Start by reproducing the example in VS Code and inspect the document symbols handler, which the issue identifies as the source of the outline response. Verify how symbols are collected and confirm that the completed change makes targetScope appear in the document outline alongside the parameter.

Written by the indexing model from the issue text.