[vtadmin] Tidy up /settings (née /debug) page

[doeg]

Signed-off-by: Sara Bee 855595+doeg@users.noreply.github.com

Description

Some tidying up before GA, but this is also (sort of) a prerequisite for single-component VTAdmin (#10118 and #10214).

Specifically, with single-component VTAdmin, the front- and back-end will (by definition) share the same "route space". (This is a downside, but not a big one.) vtadmin-api already defines several /debug routes. While it doesn't have a handler for the root /debug route, it just seemed weird and unnecessary to have vtadmin-web overlap when it doesn't really need to.

Here's what this PR does instead:

• Avoids route overlap by moving the /debug view to the /settings route, since that's likely a route we will use ✨ someday ✨ for user preferences (dark mode, time formatting, etc.) and seems like a fair place for this kind of debug info, too.

• Omits the """style guide""" (I use that term loosely, lol) for production builds, since it's only really useful in dev mode. It also makes the production build a lil smaller and simpler.

• Removes the "Debug" link from the NavRail, since this "settings page" in current form (just a blob of NODE_ENV json) isn't relevant to anyone except those that already know about it. 🔮

Here's what it looks like now for a prod build (on my local machine):

Related Issue(s)

Checklist

• "Backport me!" label has been added if this change should be backported
• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

N/A

[github-actions]

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[ajm188]

lgtm! my only question is if we should rename Debug.tsx to Settings.tsx to match the route, but i defer to you!

[doeg]

my only question is if we should rename Debug.tsx to Settings.tsx to match the route

Oh thanks for catching that!