Bug: Studiomdl produces "sticky" vertices with flex-animated models

[koerismo]

Describe the bug

Studiomdl appears to attempt to optimize meshes by removing duplicate vertices whenever possible. While this normally works well, it causes overlapping flex-affected vertices to become merged and animate improperly when flex animation is applied.

This could be resolved with a command that disables this optimization and/or with a check for vertex/flex animation that accounts for flex motion.

To Reproduce

1. Create a model with vertices that overlap in the reference model and which separate when a flex is applied.
2. Compile the model.
3. Open the model in HLMV and preview the flex.

Issue Map

N/A

Expected Behavior

Vertices that overlap should not be merged when they are able to be separated with flex animation.

Operating System

Windows 10