Add stl support

[Rushmore75]

• STLs load
• clippy is happy

Somewhat related to #78

Got slightly carried away in src/inline.rs and abstracted some logic into a from in src/model.rs. But besides that this just adds stl support. It looks like gltf support basically already exists, but I don't have a gltf model on hand to test it.

[orhun]

Looks good! Just had a question about which library to use here.
I saw bevy_stl and thought that it might be used since we already use bevy. Additionally, I saw that we already depend on some code from it.

Also, can you do the following updates:

• Update the RGP protocol spec based on this new support. Should be quick to do :)
• Do you have a cool STL model that we can include in assets/objects for demo purposes?

[orhun]

Another thing that I realized: I could not use a STL file in place of the cursor. I think this implementation only supports placing STL objects via RGP protocol.

[orhun]

nit: we could just one entry such as */**/target (don't remember the exact syntax) instead of ignoring each target directory

[Rushmore75]

• support stl for cursor
• update RGP protocol spec
• figure out target .gitignore
• find / create demo stl

[Rushmore75]

That should solve all those issues if you would like to test again

[orhun]

Looks good :)

I tried this STL file for the cursor: https://p.orhun.dev/teamug.stl

But couldn't get it to work properly:

Peek.2026-06-15.00-53.mp4

Any ideas?

P.S. can you resolve conflicts? 👼🏼

[Rushmore75]

When I open that STL in blender it also has the large plane below it. So I think that it's rendering as-intended 🤔

[orhun]

Oh I see, I'll try with a different model!
In the meantime, can you run cargo fmt and commit the changes?

[orhun]

thanks!

I just gave this a try and it works! There is no texture loading yet it seems like, but this should be a good start already :)