Add debug messages

@byCedric says:

Looks awesome! I'll test run it this weekend too. One thing that could help during development/debugging is adding `debug` messages. With that, the code path should be visible. (e.g. [this](https://github.com/micromark/micromark/blob/ac44b027357e36694efd2c59babba1b89515e73c/lib/util/create-tokenizer.mjs#L109))

Refs: https://github.com/conventional-commits/parser/pull/1