fix(list): support two-line content in inset items

[rdlabo]

Summary

• stack unslotted labels and notes in inset list items to support two-line content
• preserve wrapped labels while aligning labels and notes to the start of the item
• apply platform-specific horizontal insets to notes below iOS and Material lists
• refresh the settings and item-list demos with iOS and Material structured-content examples
• import IonListHeader through the demo shared Ionic exports

Verification

• npm run build
• cd demo && npm run build
• staged files formatted by the pre-commit hook
• npm run lint still reports only the existing generated HTML files demo/ios/App/App/public/index.html and demo/playwright-report/index.html

[github-actions]

Playwright test results

 90 passed

Details

 90 tests across 2 suites
 1 minute, 51 seconds
 4754431
 This detailed result covers Ionic 9 only. Ionic 8 runs against the same screenshots in a separate matrix job; check the workflow run for both results. To update the screenshots, comment with /update-screenshots.

[github-actions]

📊 Ionic 9 Playwright Test Report

View the detailed Ionic 9 report: https://rdlabo-dev.github.io/ionic-theme-ios26/pr-115/

Ionic 8 runs against the same screenshots in a separate matrix job. View both results in the workflow run.

[github-actions]

📊 Ionic 9 Playwright Test Report

View the detailed Ionic 9 report: https://rdlabo-dev.github.io/ionic-theme-ios26/pr-115/

Ionic 8 runs against the same screenshots in a separate matrix job. View both results in the workflow run.

[github-actions]

📊 Ionic 9 Playwright Test Report

View the detailed Ionic 9 report: https://rdlabo-dev.github.io/ionic-theme-ios26/pr-115/

Ionic 8 runs against the same screenshots in a separate matrix job. View both results in the workflow run.

[github-actions]

📊 Ionic 9 Playwright Test Report

View the detailed Ionic 9 report: https://rdlabo-dev.github.io/ionic-theme-ios26/pr-115/

Ionic 8 runs against the same screenshots in a separate matrix job. View both results in the workflow run.

[rdlabo]

/update-screenshots

[github-actions]

✅ Screenshots have been updated successfully!

The new screenshots have been committed to this PR.

[github-actions]

📊 Ionic 9 Playwright Test Report

View the detailed Ionic 9 report: https://rdlabo-dev.github.io/ionic-theme-ios26/pr-115/

Ionic 8 runs against the same screenshots in a separate matrix job. View both results in the workflow run.