Property editor composition rewrite for Umbraco 17

[Luuk1983]

📋 Description

This is a rework of the pages that combined describe the part that make up a Property Editor. It covers an overview page, a page about the Property Editor UI and the Property Editor Schema.

• I did not touch the Data Sources article that's also part of the Property Editor composition. This is a quite niche concept and I felt like that article is good enough for now (discusses with Mads).
• I created new articles for the extensions of the property editor ui and property editor schema under the extension type section. These articles describe all settings into detail. I felt like the Property Editor articles would get too bloated if they also needed to deal with the complete configuration options. BEWARE!! These two articles (although verified against the source code) are AI generated.

📎 Related Issues (if applicable)

Fixes #7603

✅ 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 17

Deadline (if relevant)

[AndyButland]

This is great @Luuk1983. I just had a few comments on the wording in a few places where I though it was a either a little repetitive or vague, but mostly seems to me you and your AI helper have done a really good job here. I don't see any factual issues at all, so just have a few tidying up suggestions.

[Luuk1983]

@AndyButland, I processed your comments (and fixed the reviewdog warnings). If the changes are OK, could you please approve the PR? :)

[AndyButland]

Yes, thanks for the updates @Luuk1983 - approving now.