docs: chunk expansion examples (#3482)

* chore: pin docling-core 2.77.1 and update uv.lock

Co-authored-by: Cesar Berrospi Ramis <ceb@zurich.ibm.com>
Signed-off-by: odelliab <odelliab@il.ibm.com>
Signed-off-by: Cesar Berrospi Ramis <ceb@zurich.ibm.com>

* change serializer

Signed-off-by: odelliab <odelliab@il.ibm.com>

* docs: remove reference to local absolute paths

Signed-off-by: Cesar Berrospi Ramis <ceb@zurich.ibm.com>

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Signed-off-by: odelliab <odelliab@il.ibm.com>
Signed-off-by: Cesar Berrospi Ramis <ceb@zurich.ibm.com>
Co-authored-by: Cesar Berrospi Ramis <ceb@zurich.ibm.com>