Remove the "Features" sections in the sidebar

[tr0njavolta]

Description

Removes the "Features" sections of the UXP and Spaces dropdowns. Moves docs to their respective new homes in "Concepts" or "Howtos". Updates Redirects

Type of change

• Bug fix (typo, broken link, incorrect info)
• Content update (new info, clarification, reorganization)
• New content (new page, section, or guide)

Checklist

• I ran make lint locally (or will fix Vale suggestions in review)
• Links work and point to the right places
• If this adds new content, I tested the examples/instructions

Additional notes

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Project	Deployment	Review	Updated (UTC)
docs	Ready	Preview, Comment	Jan 5, 2026 5:20pm

[jeanduplessis]

It doesn't have to be a blocker for this PR, but we might want to re-visit how we show paid features in the sidenav

It's a bit of a mess on Spaces specifically. All of Spaces is paid, so it doesn't make sense in the way it is represented right now.

[tr0njavolta]

It doesn't have to be a blocker for this PR, but we might want to re-visit how we show paid features in the sidenav
It's a bit of a mess on Spaces specifically. All of Spaces is paid, so it doesn't make sense in the way it is represented right now.

Agreed, I'll open a new PR for the paid features and weighting.