feat: add TransformPart class for *PART data transformation

[koubaa]

To track which file a certain PART ID (PID) after ID transformation came from:

for kw in deck.get(type="PART"):
    if target_pid in kw.parts["pid"].values:
        print(kw.included_from)  # -> the file this PART (and its transformed pid) came from

[RaphaelHeiniger]

Handling it via the transformation handler is a good idea. It will enable the user with the existing tool kit.