Fix remote data operations docs issues

[mkamiishi]

Summary

Fixed four documentation issues in the remote data operations topic.

Changes

• Replaced the duplicated IgcForOfState.chunkSize reference with IgcForOfState.startIndex in the Infinite Scroll section.
• Fixed the formatting in the Known Issues and Limitations section so that the introductory sentence is not rendered as a bullet item.
• Fixed a typo from bellow to below in the Remote Paging section.
• Moved the RowIslands setup sentence into the HierarchicalGrid component block so it only appears for the Hierarchical Grid documentation.

Notes

This is a documentation-only correction.

Checklist:

• check topic's TOC/menu and paragraph headings
• Include TOC topic labels in the topic content when it has a valuable update, is new, or is considered preview / beta
• link to other topics using ./page.mdx or ../relative/path.mdx (.mdx extension required)
• at the References section at the end of the topic add links to topics, samples, etc
• reference API documentation instead of adding a section with API

• use valid component names - [Data] Grid, IgxSelectComponent, <igx-combo>
• use spell checker tool (VS Code, Grammarly, Microsoft Editor)
• add inline code blocks for the names of classes / tags / properties
• add language descriptor for the code blocks
• check if links function by running the check-api/mdx npm commands
• check if sample is working and fully visible in the topic
• check if sample is working and fully visible in the StackBlitz
• check if code blocks match the code in StackBlitz demo
• add or update meaningful llms.description metadata and run npm run check:llms-metadata

• follow SEO guidelines to fill topic's metadata (SEO guidelines)

• do not resolve requested changes (leave that to the reviewer)

[mkamiishi]

Hi @ChronosSF,

I found a few minor documentation issues in the remote data operations topic and fixed them in this PR:

• Replaced the duplicated IgcForOfState.chunkSize reference with IgcForOfState.startIndex in the Infinite Scroll section.
• Fixed the formatting in the Known Issues and Limitations section so that the introductory sentence is not rendered as a bullet item.
• Fixed a typo from bellow to below in the Remote Paging section.
• Moved the RowIslands setup sentence into the HierarchicalGrid component block so it only appears for the Hierarchical Grid documentation.

Could you please review this PR when you get a chance?

Thanks!