[Feature Request] Configurable Code Lens position

## Problem
For a few years now, a feature request has been poping up at VS team, VS Code team, and here at omnisharp-vscode about the position of Code Lens, specifically to have it above attributes. It is my understanding that the current location is by design and that not being able to configure it is also by design. I have read and disagreed with arguments for the former, but not seen any arguments for the latter.

Personally I dislike the current inconfigurable design so much that I'm sometimes willing to have 140 column width lines **just** to have the attribute in the same line as the property/method declaration. It's horribly ugly, but IMO more readable in certain circumstances.

## Current behavior
Code Lens acts as a separator between the member and its attributes/comments.


I have to choose between this:

and this:

## Proposed behavior
### Proposal 1

I propose making the maximum number of lines that Code Lens can appear above the declaration configurable, with 0 as default.
This means that Code Lens appears at the top unless the number of lines of attributes/comment above the declaration exceeds the given number, in which case the Code Lens will appear right above the declaration.
I also propose making separate configurations for `# references` and `run test | debug test`, making this possible:

### Proposal 2
Being able to configure Code Lens to appear inline, mentioned in #4551 and microsoft/vscode#23652 like so:

### Proposal 3
Another proposal in #4551 and microsoft/vscode#23652 about placing references in the gutter:

### Final Proposal
If all the feature requests up til now and proposals are a no go, then at least please consider making a public API for configuring Code Lens for C# so that extension developers can make this possible.

Here's the closest we have gotten to making this a reality:
#1938
#429

Please consider!