Add missing docs for requestFormReset API

[smg99]

Fixes#8529

Summary

• Add a new React DOM API reference page for requestFormReset
• Document signature, parameters, return value, caveats, and usage
• Add requestFormReset to the React DOM APIs index page
• Add requestFormReset to the reference sidebar navigation

Why

The issue reports that requestFormReset is a React 19 API without a dedicated docs page. This PR adds the missing page and links it into the docs navigation so the route is discoverable.

Validation

• Ran yarn lint (passes; existing unrelated warnings only)
• Ran yarn lint-heading-ids (passes)

[smg99]

Requesting review for this docs addition.

I added:

• a new requestFormReset API reference page,
• a link in the React DOM APIs index,
• and a sidebar entry so the page is discoverable.

I also ran local checks (yarn lint and yarn lint-heading-ids). Happy to adjust wording, examples, or caveats based on maintainer feedback.

[github-actions]

Size changes

Details

📦 Next.js Bundle Analysis for react-dev

This analysis was generated by the Next.js Bundle Analysis action. 🤖

One Page Changed Size

The following page changed size from the code in this PR compared to its base branch:

Page	Size (compressed)	First Load
/[[...markdownPath]]	130.02 KB(🟡 +18 B)	245.17 KB

Details

Only the gzipped size is provided here based on an expert tip.

First Load is the size of the global bundle plus the bundle for the individual page. If a user were to show up to your website and land on a given page, the first load size represents the amount of javascript that user would need to download. If next/link is used, subsequent page loads would only need to download that page's bundle (the number in the "Size" column), since the global bundle has already been downloaded.

Any third party scripts you have added directly to your app using the <script> tag are not accounted for in this analysis

Next to the size is how much the size has increased or decreased compared with the base branch of this PR. If this percentage has increased by 10% or more, there will be a red status indicator applied, indicating that special attention should be given to this.