chore: prepare WIP for React upgrade to 17.0.2

[bosun-ai]

Summary

Prepare for upgrading React from ^16.8.4 to 17.0.2. This is a work-in-progress draft PR to outline the planned upgrade and track follow-ups. No application code or dependency changes have been committed yet.

Changes

• Added .nvmrc specifying Node 12 to standardize local development environment during the upgrade.

Context and Plan

• Target upgrade: react to 17.0.2 (and align react-dom accordingly in a subsequent commit).
• This draft PR exists to coordinate the upgrade steps and validations before making dependency changes.

Impact/Risks

• React 17 is a mostly compatibility-focused release, but:
  • Event handling changes may affect custom event listeners.
  • Updated peer dependency expectations may require updates to react-dom and test tooling.
  • Build tooling (babel/eslint/testing libraries) may need minor adjustments for compatibility.

Follow-up Work

• Update package.json dependencies:
  • react: 17.0.2
  • react-dom: 17.0.2
• Audit and update related tooling as needed (babel presets, ESLint plugins, testing libraries).
• Run full test suite and application smoke tests.
• Verify event delegation changes do not impact existing components.
• Update documentation if any developer workflow changes are required.

Reviewer Notes

• This PR is a work in progress; do not merge.
• No code changes to review yet beyond .nvmrc.

Action Items

• Confirm Node 12 is the intended baseline for this upgrade or adjust .nvmrc as needed.
• Approve the upgrade plan and identify any repos or packages that must be upgraded in lockstep.
• Call out areas of the codebase sensitive to event handling changes in React 17.

References

• React 17 release notes: https://reactjs.org/blog/2020/10/20/react-v17.html

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This pull request is created by bosun, a code maintenance automation platform. For more information, visit bosun.ai.