Route to transform 2d image (depth map) into a curved bracelet (and STL file)?
This may not be your cuppa tea, but if you're willing to learn to use OpenSCAD or already know how, there's a Thingiverse post that appears to directly address your objective.

Correction, this particular post on Thingiverse consists of a series of Python files, of which I have zero experience/qualifications. It may still be of value, if you are Python capable.



Another resource that is strictly OpenSCAD is from Eric Buijs, a rather talented 3D design person. His YouTube channel has a number of useful tutorials for both OpenSCAD and Solvespace. This video in particular describes applying a flat object to a curved one using OpenSCAD, resulting in a lithophane.



As I created this answer, I did not re-watch the 12+ minute video, but I recall how he explains clearly how the program dissects the surface into a number of flat panels and then superimposes the image on each segment. From this presentation, I suspect one could expand to a full cylinder.