Enhance state persistence documentation for various platforms

[TomoyaWashio]

• Improved clarity and formatting in the state persistence section for Angular, React, WebComponents, and Blazor.
• Added detailed explanations for methods related to state management, including getState, applyState, and applyStateFromString.
• Updated examples to demonstrate saving and restoring grid state using local storage and session storage.
• Clarified limitations regarding the persistence of column templates and pivot configurations.
• Included additional code snippets for restoring grid state in Blazor and Angular applications.

Closes #

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)