add post chunking strategy

[tbs17]

this draft PR in unstructured intends to do below:

• modified dispatch.py for the chunk() to include contextual_chunking_spec to fetch chunker func chunk_by_contextual in core-product

[sentry[bot]]

🔍 Existing Issues For Review

Your pull request is modifying functions with the following pre-existing issues:

📄 File: unstructured/chunking/dispatch.py

Function	Unhandled Issue
wrapper	LookupError: unknown encoding: string /general/v0... Event Count: 2

---

_{Did you find this useful? React with a 👍 or 👎}