Test URL variables in design

[PClmnt]

Description

This PR adds the ability for users to test their URL variables. When building screens with dynamic URL parameters (like /employees/:id), this lets the user provide an example value so they can see how it affects the screen

Also, to make it easier to understand what is needed, the placeholder is based on the route of the screen, so say for /employees/:test/validate/:id, the placeholder field shows an example like "1/validate/2".

Screenshots

Screen.Recording.2025-02-11.at.13.34.38.mov

Launchcontrol

• Adds a input within the screen settings that enables the testing of URL variables within the design section.

Feature branch env

Feature Branch Link

[qa-wolf]

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[aptkingston]

Nice work Pete. I played around with this locally and couldn't find any issues with it functionally. It handled everything I threw at it, so nice job 👌

Just a few style points:

• We shouldn't show this at all if your screen doesn't use any URL params. Right now it always shows, but serves no purpose if you aren't using any params
• Is it worth updating the copy slightly to make it clear it's temporary? With the new state panel we are very explicit with "Set temporary value for design preview". This is basically an identical feature for URL params. I'm not totally set on this though - I don't really mind either way.
• Style wise it's a bit unique, but that's probably fine. It might be nice to at least align it with our other settings though, which would mean making hardcoded prefix section 98px wide rather than 40%. Could we maybe update the label to be the same colour as the rest of the settings labels too? And probably also update the casing to remove the capital letters other than the first one.

[aptkingston]

LGTM!