LTX in Rust

I was very impressed by LTX model and its capabilities so I have put substantial effort into getting it to run and laying the groundwork for rust native implementation of LTX.

So I integrated first class LTX model support into our Rust based training and inference engine called brain: https://github.com/swedishembedded/brain

Brain already has a serious native-Rust LTX-2.5 inference engine, not merely an experimental port. For distilled T2V/I2V and synchronized A/V it is quite capable. It is not yet a complete LTX-2.5 implementation because several of 2.5's defining higher-level features - especially real DFR and native multishot - and much of the bidirectional audio/video + LoRA ecosystem remain to be done.

But we have a start and it's a very good one so far.