Fix unnecessary DOM mutations in updateInput for unchanged inputs (#36229)

[aryashashank]

Summary

Fixes #36229

React 19 introduced a performance regression in updateInput() (ReactDOMInput.js). On every commit, the function unconditionally performs three DOM mutations for every <input> element — even when none of the input-specific props (type, name, value, checked) have changed:

1. node.name = '' — disconnects the input from its radio group
2. node.type = type — rewrites the type property
3. node.name = name — restores the name property

On pages with many <input> elements (e.g. 500+), this causes hundreds of unnecessary DOM writes per render, making updates significantly slower than React 18.

This PR adds change detection by comparing new values against the current DOM state before writing. The node.name = '' disconnection trick — which exists to ensure atomicity when changing type or name alongside checked for radio buttons — is now only performed when type or name is actually changing. All existing semantics, including radio button group behavior, are preserved.

How did you test this change?

Added two new tests to ReactDOMInput-test.js:

1. "should not perform unnecessary DOM mutations for unchanged inputs" — Renders two inputs under a shared parent, installs an Object.defineProperty setter trap on the unchanged input's name property, then updates only the first input's value. The test verifies that the second input's name is never written to.

2. "should not write type or name when they have not changed" — Renders an input, installs a setter trap on type that counts writes, then re-renders with identical props. The test verifies zero writes to type.

Ran the full test suites:

$ node scripts/jest/jest-cli.js packages/react-dom/src/tests/ReactDOMInput-test.js
Test Suites: 1 passed, 1 total
Tests: 126 passed, 126 total

$ node scripts/jest/jest-cli.js packages/react-dom/src/tests/ReactDOMServerIntegrationInput-test.js
Test Suites: 1 passed, 1 total
Tests: 35 passed, 35 total

ESLint and Prettier also pass on the changed files.

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