[6.x] Render rich Form API field instructions

[riasvdv]

Description

Form API field instructions displayed Markdown and inline HTML as plain text in Vue forms. Generate instructionsHtml through the existing tip/warning notice parser and render it through the help-text slot, retaining plain-text fallback and the field's existing accessibility association and instructions positioning. Update the shared PHP/Vue payload fixture for the new property.

Field instructions → existing notice parser → instructionsHtml → help-text slot

Related issues

• Extracted the field instructions changes from [6.x] Form component compatibility #19665.

[github-actions]

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[github-actions]

This PR had conflicts with 6.x. Claude attempted an automatic resolution and pushed a merge commit. Please review the merge commit carefully before approving/merging.

Claude's response

I resolved the one conflict in the merge from 6.x and committed it as 36deb7f. Nothing has been pushed.

The conflict was in CHANGELOG.md. Both sides had added a different "Fixed" entry at the same place in the list: this branch's entry for #19771 (Form API field instructions showing Markdown and inline HTML as plain text) and 6.x's entry for #19767 (money input fixes). They describe unrelated fixes, so I kept both, with #19771 first and #19767 right after it. Nothing was ambiguous, so I didn't add any CONFLICT-REVIEW comments.

The other two files changed by the merge, resources/js/pages/settings/workflows/Index.vue and resources/templates/_includes/forms/money.twig, merged cleanly and I didn't edit them.

Changed

• CHANGELOG.md: removed the conflict markers and kept both entries.
• Merge commit 36deb7f created with git commit --no-edit.

Found

• Nothing.

[github-actions]

This PR had conflicts with 6.x. Claude attempted an automatic resolution and pushed a merge commit. Please review the merge commit carefully before approving/merging.

Claude's response

I resolved the merge from 6.x and committed it as c565377. I haven't pushed it.

There was only one conflict, in CHANGELOG.md. Both sides had added a different "Fixed" entry at the same spot in the changelog:

• This branch: the entry for [6.x] Render rich Form API field instructions #19771 (Form API field instructions showing Markdown and inline HTML as plain text).
• 6.x: the entry for [6.x] Preserve settings input and errors after failed saves #19775 (failed settings saves losing input and validation errors).

The entries don't depend on each other, so I kept both, with this branch's entry first, then the 6.x one. No other lines changed. Every other file from 6.x merged cleanly.

None of this was ambiguous, so I didn't leave any # CONFLICT-REVIEW: comments.