Support Dart VSCode getFlutterSdkCommand

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Is your feature request related to a problem? Please describe.

On each flutter update, fvm must change .vscode/settings.json

  // settings.json
  "dart.flutterSdkPath": ".fvm/versions/3.29.0",

Describe the solution you'd like
Dart Code introduced a new configuration:

getFlutterSdkCommand and getDartSdkCommand
Dart-Code/Dart-Code@b1f79db

If fvm implements a simples fvm path, fvm which or fvm where, it would simplify setup IMHO