fix(ui_firestore): fixed pagination issue

[a-s-k-u]

Description

Current Behavior: Excessive Document Querying on Page Change Upon each page transition, the package is querying not only for the documents on the current page but also for all preceding documents. This leads to an unnecessary increase in total read operations from Firebase.

The Solution: This pull request implements the usage of Firebase Firestore query cursors to exclusively retrieve data pertaining to the current page, optimizing data retrieval. When the page size changes, the package no longer re-fetches from first page.

Related Issues

This PR will resolve Pagination Issue.

Checklist

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• [x] I read the Contributor Guide and followed the process outlined there for submitting PRs.
• [x] My PR includes unit or integration tests for all changed/updated/fixed behaviors (See Contributor Guide).
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• [x] All unit tests pass (melos run test:unit:all doesn't fail).
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Breaking Change

Does your PR require plugin users to manually update their apps to accommodate your change?

• [ ] Yes, this is a breaking change.
• [x] No, this is not a breaking change.