Push SDK paths onto Terminal environment PATH

Fixes #2209, but currently a bit doesn't currently work well because of microsoft/vscode#99878.

src/extension/extension.ts

@@ -187,6 +187,13 @@ export async function activate(context: vs.ExtensionContext, isRestart: boolean
  analytics.flutterSdkVersion = sdks.flutterVersion;
  }
 
+ // Add the PATHs to the Terminal environment so if the user runs commands
+ // there they match the versions (and can be resolved, if not already on PATH).
+ let envPathPrefix = `${sdks.dart}${path.delimiter}`;
+ if (sdks.flutter)
+ envPathPrefix += `${sdks.flutter}${path.delimiter}`;
+ context.environmentVariableCollection.prepend("PATH", envPathPrefix);
+
  if (config.previewLsp || process.env.DART_CODE_FORCE_LSP) {
  isUsingLsp = true;
  }