Introduce utilities section for Backoffice customization helpers

[madsrasmussen]

📋 Description

We have a lot of code helpers that can be used when customizing the Backoffice. They aren’t really foundation or extension types but something that can be optionally used to ease the implementation.

This PR introduces an “Utilities” section inside the Customizing section for this type of documentation. I have moved the first two articles into this area that didn’t really fit where they were positioned at the moment:

• Confirm dialog
• UI sorting

✅ Contributor Checklist

I've followed the Umbraco Documentation Style Guide and can confirm that:

• Code blocks are correctly formatted.
• Sentences are short and clear (preferably under 25 words).
• Passive voice and first-person language (“we”, “I”) are avoided.
• Relevant pages are linked.
• All links work and point to the correct resources.
• Screenshots or diagrams are included if useful.
• Any code examples or instructions have been tested.
• Typos, broken links, and broken images are fixed.

Product & Version (if relevant)

Umbraco CMS v17

Deadline (if relevant)

Umbraco CMS v17

📚 Helpful Resources

• 🧾 Umbraco Contribution Guidelines
• ✍️ Umbraco Documentation Style Guide

[AndyButland]

Looks good to me and see the redirects are in place.