Add option "end" to the slider's origin property next to "start" and "center"

[danieledler]

🚀 Feature request

Add option "end" to the slider's origin property, next to the options "start" and "center".

🧱 Problem Statement / Justification

The origin property of the slider sets the start position of the filled part of the track. The current options are "start" (default) and "center". However, I'm missing the option "end".

The "end" option would be useful when the value represents an offset from the end.

For example, if the slider is used to set a threshold value between 0 to 100 to include values above it, it makes more sense to have the values above the thumb highlighted with a filled track instead of the values below it.

✅ Proposed solution or API

I have a solution here and will make a pull request.

↩️ Alternatives

I considered using the support for right-to-left direction (dir="rtl") but I needed to wrap the slider in a locale with right-to-left direction which also has side-effects on labels.