feat: support React 19 for Cypress Component Testing

[AtofStryker]

• Closes Support React 19 in Component Testing #29470

Additional details

Adds React 19 (Not yet officially released) and React 19 Release Candidate support to component. This PR is prematurely supporting React 19 for Component testing as we do not anticipate massive release candidate API changes with React 19. React 19 Release Candidate support is also needed to support Next 15 (not 15 RC, but actual 15).

Testing the build binaries works as expected against a sample React 19 project. This works OOTB since the ReactDOM.render() changes merged upstream into cypress/react in #30590, so no custom test harness is needed 🎉

Using the React 19 RC today with Cypress 13x

Since React 19 is not supported today, framework detection does not work correctly and scaffolded dependencies are not satisfied

The cypress/react test harness also does not work as ReactDOM.render() was removed in React 19. The user can use cypress/react18 to get this to work, but that is not obvious.

Using the React 19 RC on this branch

Dependencies are automatically detected and satisfied. This is partially due to use detecting the release candidate, which I think we can announce we will remove once React 19 is officially released without releasing a breaking change. This requires further discussion

The cypress/react test harness works with 19 naturally because it uses the rendering methods used by react 18, which is root.render() from the ReactDOM/client package so no change is necessary

Steps to test

Highly recommend setting up a sample React 19 project. This is likely easiest with setting up a React project with Vite and then updating the React dependencies following this guide.

How has the user experience changed?

Users can now use Cypress Component Testing with React 19 in Cypress 14

PR Tasks

• Have tests been added/updated?
• Has a PR for user-facing changes been opened in cypress-documentation? chore: add docs for react 19 and next.js 15 cypress-documentation#6008
• Have API changes been updated in the type definitions?

[cypress]

cypress    Run #58529

Run Properties:   Passed #58529  •  cd07b42d6c: feat: support react 19 for component testing with cypress/react [run ci]

Project	cypress
Branch Review	feat/support_react_19
Run status	Passed #58529
Run duration	17m 44s
Commit	cd07b42d6c: feat: support react 19 for component testing with cypress/react [run ci]
Committer	AtofStryker
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Test results
Failures	0
Flaky	4
Pending	1103
Skipped	0
Passing	15855
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[AtofStryker]

these peer dependencies are slightly off since they don't match the release candidate semver, which is not a problem with the shipped binary but could cause problems if someone is trying to install @cypress/react with the react 19 release candidate. I don't see anyone actually needing to do this, and especially since React 19 isn't officially released yet, I am hesitant to make the change here.