• Closes Allow injecting into non-dependency code #14

Replaces ModuleMatcher struct with a CodeMatcher enum which allows matching to both dependency code and absolute paths.

This changes the matching API. Now you always pass the absolute path to the file and can optionally include the dependency details if this file is in a dependency in node_modules.

So the JavaScript API would change to something like this:

interface InstrumentationMatcher {
  // If this returns undefined, we know there's no transforming required for this specific file
  getTransformer(absolute_path: string, dependency?: { name: string, version: string, relative_path: string }): Transformer | undefined;
}