Feat: Guard: Roslyn Analyser / Code fix / suggestion / Quick Fix

### Overview

Diagnostic.Guard:

- In visual studio i would like to have Quick Fix suggestions for method parameters

Quick Fix Example:
- A method parameter of type List, will suggest to make the NotNull Gard code below in the method body.
- etc. For all types.
- Could also work for variables and constructors

### API breakdown

I dont know

### Usage example

I dont know enough..

### Breaking change?

No

### Alternatives

I dont know

### Additional context

_No response_

### Help us help you

No, just wanted to propose this