No local name suggestions in top-level code

### Version
VS Code: 1.101.0
C# Extension: 2.82.12

### Steps to reproduce

1. Open a new console project with a top-level `Program.cs` file.
2. Add a new local using a custom type, such as `List`
4. Observe not getting a suggestion.
### Expected Behavior

`people` is suggested for the local of type `List`.

This is the behavior in other contexts, such as in a simple `void M() { }` local function in the top-level code.

### Actual Behavior

Nothing is suggested.