Refactor the `actor.sh` script to modularize functions for finding the Apify CLI, setting up a temporary environment, and cleaning it up. Introduce a new function, `get_actor_input()`, to handle input detection more robustly. Replace inline Python conversion logic with an external script, `docling_processor.py`, for processing documents via the docling-serve API.
Signed-off-by: Václav Vančura <commit@vancura.dev>
