LLM now only parses username + contribution types (strict 2-field JSON).
Project detection is fully deterministic from file paths:
tinytorch/ → tinytorch, book/ → book, kits/ → kits, labs/ → labs
If project cannot be determined, the bot asks the user instead of
silently defaulting to book. Also removes @AndreaMattiaGaravagno
from book/.all-contributorsrc (was incorrectly added there by the
old workflow — their PR only touched tinytorch/ files).
0be9325fbe