docs: use role attribute for since badges in headings

[tomivirkki]

Summary

• Follow-up to docs: prefer role-attribute since badge on section headings #5787, fixing the remaining 11 section headings that still wrap their titles in inline [since:...]#...# spans instead of using the [role="since:..."] attribute form established there.
• The inline span form isn't supported in ==–==== headings and currently renders as a blank badge, so these version indicators were invisible to readers.

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[github-actions]

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URL: https://docs-preview-pr-5834.fly.dev

Changed pages

Added content is highlighted in green; removed content is marked in red on each page.

• components/auto-grid — modified, +4/-2 lines, 2 removal marker(s)
• components/text-field — modified, +2/-1 lines, 1 removal marker(s)
• flow/advanced/downloads — modified, +2/-1 lines, 1 removal marker(s)
• flow/binding-data/data-provider — modified, +2/-1 lines, 1 removal marker(s)
• flow/component-internals/element-api/calling-javascript — modified, +4/-2 lines, 2 removal marker(s)
• flow/i18n — modified, +2/-1 lines, 1 removal marker(s)
• flow/routing/navigation — modified, +2/-1 lines, 1 removal marker(s)
• flow/routing/page-titles — modified, +2/-1 lines, 1 removal marker(s)
• tools/copilot — modified, +2/-1 lines, 1 removal marker(s)

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