Provide support for animating via .fbx/dmx files

[Arhowk]

The new animation function is great for creating sequences based on already existing animations, but it still lacks the ability to create fully custom animations. Since we do not have the source files for the existing heroes, the only workaround for this is to re-import the heroes from Source 1 which is a tedious process prone to failure at the slightest mistake. Since we already have the ability to animate Source 2 models in S2FM and export it to a .smd/fbx/dmx file, it would be nice to have one of the following

1. Allow a file path input to model:CreateSequence to specify the smd/fbx/dmx file to load from rather than reading from a pre-existing animation on the model
2. Expose the source files for .vmdl_c (atleast for heroes) or allow the editing of their "Animations" block if possible
3. Provide some override manifest file to dynamically insert custom animations into existing vmdl files

If there's already something existing that can do this than information about it would be appreciated (as it is currently undocumented besides re-importing). As appreciated would be a simple "Not possible / Not going to happen" comment to get used to the re-importing process.

[DoctorGester]

Since I wrote an NTRO editor tool to override .vanim_c files I think it's not really hard to create a tool to override .vagrp_c files, adding links to new .vanim_c files, but there might be potential pitfalls and I'm pretty sure an animation has to be compiled first and not sure if that can be done independently.

So yeah something built-in would be really really cool to have.