Transformer doesn't work with arrow and anonymous functions

[nandanmen]

The worker throws errors when the user uses arrow functions in their algorithm. Specifically there are two cases to consider here:

• Default exporting an arrow function
  • When a user default exports an arrow function instead of a regular function declaration, the worker throws an error with the message Expected type "FunctionDeclaration" with option {}, but instead got "ArrowFunctionExpression"
• Default exporting an anonymous function
  • When a user default exports an anonymous function, e.g. function (a, b), then the worker throws a rather unclear error: unknown: Property name expected type of string but got null
• Assigning arrow functions
  • When assigning arrow functions with a debugger statement in that function, the worker fails with a DataCloneError because the snapshot records the function itself as part of the available scope