chore: process chipper hierarchy

[qued]

PR to support schema changes introduced from PR 232 in unstructured-inference.

Specifically what needs to be supported is:

• Change to the way LayoutElement from unstructured-inference is structured, specifically that this class is no longer a subclass of Rectangle, and instead LayoutElement has a bbox property that captures the location information and a from_coords method that allows construction of a LayoutElement directly from coordinates.
• Removal of LocationlessLayoutElement since chipper now exports bounding boxes, and if we need to support elements without bounding boxes, we can make the bbox property mentioned above optional.
• Getting hierarchy data directly from the inference elements rather than in post-processing
• Don't try to reorder elements received from chipper v2, as they should already be ordered.

Testing:

The following demonstrates that the new version of chipper is inferring hierarchy.

from unstructured.partition.pdf import partition_pdf
elements = partition_pdf("example-docs/layout-parser-paper-fast.pdf", strategy="hi_res", model_name="chipper")
children = [el for el in elements if el.metadata.parent_id is not None]
print(children)

Also verify that running the traditional hi_res gives different results:

from unstructured.partition.pdf import partition_pdf
elements = partition_pdf("example-docs/layout-parser-paper-fast.pdf", strategy="hi_res")

[christinestraub]

LGTM!

[qued]

Ingest test diffs are caused by this change, and I think this is the sole source of diffs.

[christinestraub]

Ingest test diffs are caused by this change, and I think this is the sole source of diffs.

Yes, that's right.

[ajjimeno]

LGTM!