Add a “go fix" style tool for automated modernization of the codebases

### Is your feature request related to a problem? Please describe.
Updating large .NET codebases to newer APIs and language features is manual and time consuming.

### Describe the solution you'd like
Similar to `go fix`, create an equivalent command or tool that scans the codebase, identifies deprecated APIs and outdated patterns, and automatically applies safe refactorings (probably with a dry run option)

### Additional context