Add __REACT_DEVTOOLS_HIDE_CONSOLE__ to suppress DevTools download message

[more-shubham]

Summary

Fixes #24283

• Adds a __REACT_DEVTOOLS_HIDE_CONSOLE__ global variable that suppresses the "Download the React DevTools" console message
• Useful for remote debugging environments (CEP, nwjs-like contexts) where the Chrome extension cannot function
• Includes Flow type declaration and test coverage

Test plan

• Added unit test that verifies the message is suppressed when __REACT_DEVTOOLS_HIDE_CONSOLE__ is set to true
• Run yarn test ReactDOM-test to verify

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[Copilot]

Pull request overview

This PR adds a __REACT_DEVTOOLS_HIDE_CONSOLE__ global variable to suppress the "Download the React DevTools" console message in environments where the browser extension cannot be installed, such as CEP or nwjs-like contexts. The implementation follows React's established pattern for global configuration variables and includes appropriate Flow type declarations and test coverage.

Key Changes:

• Adds Flow type declaration for __REACT_DEVTOOLS_HIDE_CONSOLE__ as void | true
• Updates DevTools message display logic to check if suppression is enabled
• Includes test coverage to verify message suppression functionality

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
scripts/flow/environment.js	Adds Flow type declaration for the new global variable as void | true, ensuring type safety
packages/react-dom/src/client/ReactDOMClient.js	Updates conditional logic to suppress DevTools message when __REACT_DEVTOOLS_HIDE_CONSOLE__ is defined
packages/react-dom/src/client/ReactDOMClientFB.js	Applies identical suppression logic for Facebook-internal build consistency
packages/react-dom/src/__tests__/ReactDOM-test.js	Adds test case verifying message suppression when global variable is set to true

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[more-shubham]

Hi! Just checking in on this PR. Is there anything I can improve or any feedback? Happy to make changes if needed. Thanks!