chore(ci): update GitHub Actions and source Node version from .nvmrc

[oliverlaz]

🎯 Goal

Keep our CI pipeline current and remove drift between the Node version we develop against and the one CI runs. Specifically:

• The codecov/codecov-action was on v5; v6 (Mar 2026) is the first major with Node 24 support, matching the rest of our toolchain.
• Node was hardcoded as '24' in two places (the composite setup-node action and the size workflow), so a future Node bump would require touching multiple files in lockstep with .nvmrc. Single source of truth is safer.
• The size workflow ran under whatever Node the preactjs/compressed-size-action defaults to (Node 20), forcing us to set YARN_IGNORE_ENGINES: 'true' to bypass our engines requirement. That's a workaround that masks the actual problem — the job wasn't running on Node 24.

🛠 Implementation details

.github/actions/setup-node/action.yml

• Removed the node-version input (no caller was overriding it) and switched actions/setup-node@v6 to node-version-file: '.nvmrc'. .nvmrc is now the single source of truth for the Node version across all workflows that use this composite action.

.github/workflows/ci.yml

• Bumped codecov/codecov-action from v5 → v6.

.github/workflows/size.yml

• Added an explicit actions/setup-node@v6 step (also using node-version-file: '.nvmrc') before preactjs/compressed-size-action@v2, so the job's shell commands run under Node 24.
• Removed the YARN_IGNORE_ENGINES: 'true' env override now that the engines requirement is satisfied.

Audit notes (no changes needed)

• All other actions are already at the latest major: actions/checkout@v6, actions/setup-node@v6, actions/cache@v5, preactjs/compressed-size-action@v2.
• No published GitHub security advisories on any action we use.

🎨 UI Changes

N/A — CI/build configuration only, no runtime or visual changes.

[github-actions]

Size Change: 0 B

Total Size: 672 kB

ℹ️ View Unchanged

Filename	Size
dist/cjs/audioProcessing.js	1.32 kB
dist/cjs/emojis.js	3.01 kB
dist/cjs/index.js	267 kB
dist/cjs/mp3-encoder.js	1.27 kB
dist/cjs/useNotificationApi.js	45.4 kB
dist/css/emoji-picker.css	178 B
dist/css/emoji-replacement.css	456 B
dist/css/index.css	39.3 kB
dist/es/audioProcessing.mjs	1.31 kB
dist/es/emojis.mjs	2.52 kB
dist/es/index.mjs	265 kB
dist/es/mp3-encoder.mjs	756 B
dist/es/useNotificationApi.mjs	45.2 kB

_{compressed-size-action}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.79%. Comparing base (cd3a9c0) to head (59e3843).
⚠️ Report is 13 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3156   +/-   ##
=======================================
  Coverage   82.79%   82.79%           
=======================================
  Files         419      419           
  Lines       12270    12270           
  Branches     3951     3951           
=======================================
  Hits        10159    10159           
  Misses       2111     2111           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[stream-ci-bot]

🎉 This PR is included in version 14.1.0 🎉

The release is available on:

• GitHub release
• npm package (@latest dist-tag)

Your semantic-release bot 📦🚀