Entry point updates to transformer & updating to latest Analyzer

- Removes the explicit list of entry points and switches to auto-detecting entry points, following the standard pub build model.
- Updating to latest code_transformers which has the entry point detection code.
- Updating to latest Analyzer (code_transformers dependency)
- Updating transformer tests to include the main(), also took the chance to remove unnecessary files in the tests now that we can generate injectors for types within web/.