[PY] fix: streaming - citations & pyproject.toml updates

[lilyydu]

Linked issues

closes: #minor

Details

match with #2185 and #2202,

• citations is now enabled during streaming, and for the final message
• updated colour/outline pngs for sample to adhere to manifest validation
• fixed indexing for citations position
• added StreamingEntity class to fix serialization on streaminfo object
• version 2 of poetry was released which led to a few scripts failing

Attestation Checklist

• My code follows the style guidelines of this project

• I have checked for/fixed spelling, linting, and other errors

• I have commented my code for clarity

• I have made corresponding changes to the documentation (updating the doc strings in the code is sufficient)

• My changes generate no new warnings

• I have added tests that validates my changes, and provides sufficient test coverage. I have tested with:

  • Local testing
  • E2E testing in Teams

• New and existing unit tests pass locally with my changes