Revit C# API Level Snapping Plugin Development

I’m looking for a Revit C# API solution to replicate the behavior where, in an Elevation view, you can “snap” a new level’s endpoints (left/right) so they align with another level’s endpoints. When this snap/lock is in place, dragging one level’s endpoint to the left or right also moves the other level’s endpoint in sync. Essentially, there seems to be some kind of alignment or length constraint at work.

Ultimately, I want to develop a plugin where I can specify a level name, an elevation offset (distance), and a reference level for snapping—so the new level is created with its endpoints locked to the specified existing level.