feat: upgrade to React 19

[andeplane]

Supersedes dependabot PRs #277 and #278. Upgrades react, react-dom, @types/react, @types/react-dom to v19, and @testing-library/react to v16 for compatibility. Fixes all breaking changes.

[gemini-code-assist]

Summary of Changes

Hello @andeplane, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request focuses on a significant version bump for the core React libraries and their associated type definitions. The primary goal is to bring the project up to the latest React 19 standard, which also necessitated an update to the testing library to maintain compatibility. This upgrade ensures the application benefits from the newest features, performance improvements, and bug fixes introduced in React 19, while also addressing any breaking changes that arose during the transition.

Highlights

• React 19 Upgrade: Upgraded react and react-dom to version 19.0.0, along with their corresponding TypeScript type definitions (@types/react, @types/react-dom) to 19.0.0.
• Testing Library Update: Updated @testing-library/react to version 16.0.0 to ensure compatibility with React 19.
• Dependency Resolution: Resolved various breaking changes and updated transitive dependencies in package-lock.json to align with the new React ecosystem, including updates to Babel helper utilities, RC components, and scheduler.

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Changelog

• package-lock.json
  • Updated react from 18.3.1 to 19.2.4, removing its loose-envify dependency.
  • Updated react-dom from 18.3.1 to 19.2.4, updating its scheduler dependency and react peer dependency, and removing its loose-envify dependency.
  • Updated @types/react from 18.3.27 to 19.2.14 and removed its @types/prop-types dependency.
  • Updated @types/react-dom from 18.3.7 to 19.2.3 and updated its @types/react peer dependency.
  • Updated @testing-library/react from 15.0.7 to 16.3.2, adjusting its peer dependencies to support React 19.
  • Updated scheduler from 0.23.2 to 0.27.0, removing its loose-envify dependency.
  • Updated @babel/helper-plugin-utils from 7.27.1 to 7.28.6.
  • Updated @babel/plugin-syntax-jsx from 7.27.1 to 7.28.6.
  • Updated @rc-component/async-validator from 5.0.4 to 5.1.0.
  • Updated @rc-component/trigger from 2.3.0 to 2.3.1.
  • Updated rc-segmented from 2.7.0 to 2.7.1.
  • Removed loose-envify as a direct dependency from several packages.
  • Added peer: true flag to several node_modules entries including @testing-library/dom, @types/aria-query, ansi-regex, dom-accessibility-api, lz-string, pretty-format, ansi-styles, and react-is.
• package.json
  • Updated react from ^18.2.0 to ^19.0.0.
  • Updated react-dom from ^18.2.0 to ^19.0.0.
  • Updated @types/react from ^18.2.0 to ^19.0.0.
  • Updated @types/react-dom from ^18.2.0 to ^19.0.0.
  • Updated @testing-library/react from ^15.0.7 to ^16.0.0.

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[gemini-code-assist]

Code Review

This pull request upgrades React and related dependencies to version 19. While the direct dependency updates appear correct, I've identified several other dependencies in your project that are not compatible with React 19. This will likely lead to runtime errors. The most critical incompatibility is with react-fetch-hook. Please address these compatibility issues before merging.

[andeplane]

/gemini review

[gemini-code-assist]

Code Review

This pull request successfully upgrades the project to React 19 and Styled Components v6, along with their associated dependencies. This is a significant and beneficial update, bringing the project up-to-date with the latest versions of these core libraries. The changes in package-lock.json reflect the new dependency tree, including the removal of several packages that are no longer needed, which can lead to a leaner build. The adjustments in src/containers/View.tsx to use null instead of undefined for useRef initial values and assignments improve type clarity and maintainability.

[gemini-code-assist]

The react-fetch-hook package has been removed. Please confirm that its functionality is either no longer required or has been successfully replaced by alternative implementations within the codebase. This is a functional change that should be verified to ensure no regressions.