[EuiRange] Migrate to function component

[angeles-mzb]

Summary

• What: This PR refactors EuiRange from a class component to a function component.
• Why: closes [EuiRange] Migrate from class to function component #9494
• Additional changes:
  • Updated the InputWithPopover Storybook (VRT) to open the popover via user interaction.
  • Updated related VRT baselines with the focused state.
  • Replaced non-null assertion for input
  • Added kibana's prep commit to update affected snapshots and assertions. Successful build here.

API Changes

No API changes

Screenshots

Before	After
Screen.Recording.2026-09-30.at.10.27.04.mov	Screen.Recording.2026-09-30.at.10.26.06.mov

Impact Assessment

Note: Most PRs should be tested in Kibana to help gauge their Impact before merging.

• 🔴 Breaking changes — What will break? How many usages in Kibana/Cloud UI are impacted?
• 💅 Visual changes — May impact style overrides; could require visual testing. Explain and estimate impact.
• 🧪 Test impact — May break functional or snapshot tests (e.g., HTML structure, class names, default values).
• 🔧 Hard to integrate — If changes require substantial updates to Kibana, please stage the changes and link them here.

Impact level: 🟢 None

Release Readiness

• Documentation: {link to docs page(s)}
• Figma: {link to Figma or issue}
• Migration guide: {steps or link, for breaking/visual changes or deprecations}
• Adoption plan (new features): {link to issue/doc or outline who will integrate this and where}

QA instructions for reviewer

• Verify parity with current production code
• Verify the component works as expected in Storybook
• Make sure updated VRT screenshots reflect relevant changes only
• Verify prep commit is relevant

Checklist before marking Ready for Review

• Filled out all sections above
• QA: Tested light/dark modes, high contrast, mobile, Chrome/Safari/Edge/Firefox, keyboard-only, screen reader
• QA: Tested in CodeSandbox and Kibana
• QA: Tested docs changes
• Tests: Added/updated Jest, Cypress, and VRT
• Changelog: Added changelog entry
• Breaking changes: Added breaking change label (if applicable)

Reviewer checklist

• Approved Impact Assessment — Acceptable to merge given the consumer impact.
• Approved Release Readiness — Docs, Figma, and migration info are sufficient to ship.

[github-actions]

Kibana Regression Integration Test

Status: 💔 Kibana CI failed
Branch: update-dependencies/1790756707
Kibana PR: elastic/kibana#294399

Please check Kibana CI logs for details.

[weronikaolejniczak]

LGTM! 🟢 I tested and I noticed no regression. Just have 2 small comments. Thanks, Angeles!

[infra-vault-gh-plugin-prod]

💚 Build Succeeded

• Buildkite Build
• Commit: b1ffbbd

History

• 💚 Build #8176 succeeded 83a5c57
• 💚 Build #8171 succeeded cd17512

cc @angeles-mzb

[infra-vault-gh-plugin-prod]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: b1ffbbd
• Documentation website
• Storybook
• ⚠️ Visual regression tests did not complete (see build)

Failed CI Steps

• 📷 Test visual regression #1

History

• 💚 Build #5735 succeeded 83a5c57
• 💚 Build #5728 succeeded cd17512

cc @angeles-mzb