[FIX] Supporting multi chunk for large documents

What

This PR enables the following.

Support for proper response when large document is executued.

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Why

Larger docuemnts context retrival was not optimized for non zero chunks.

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How

Supporting Simple and Sub query retrieval.

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Can this PR break any existing features. If yes, please list possible items. If no, please explain why. (PS: Admins do not merge the PR without this section filled)

No, a method refactored in prompt service enables the support. ...

Database Migrations

Added a field to Choices in model. ...

Env Config

Not Applicable. ...

Relevant Docs

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Related Issues or PRs

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Dependencies Versions

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Notes on Testing

Reproducing the error - The response was proper for docuemtns with pages - 500, but the ambiguity in response happend only after pages greater that 1000.

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Screenshots

Error reproduced Screenshot from 2024-05-13 22-31-22

Fix Screenshot from 2024-05-14 14-41-53

Screenshot from 2024-05-13 18-13-45

Checklist

I have read and understood the [Contribution Guidelines]().

Zipstack / unstract