feat: add config to load more field that the schema

[samsja]

Context

the goal of this pr is to allow AnyDoc to load any protobuf file without knowing the class beforehand

code example :

from docarray.base_doc.any_doc import AnyDoc

doc = AnyDoc(hello='world')

print(f"doc= \n {doc}")
pt = doc.to_protobuf()
print(f"pt= \n {pt}")
doc2 = AnyDoc.from_protobuf(pt)
print(f"doc2= \n {doc2}")
assert doc2.dict()['hello'] == 'world'

[github-actions]

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