HPAI Workflow Step 07: Inference and Computation Choices

## Objective
Choose inference methods and computational approach.

## Considerations
- Likelihood formulation (FOI-based, continuous time)
- Latent infection times (data augmentation or marginalization)
- MCMC method (HMC/NUTS, or alternatives for discrete latents)
- Software choice (Turing.jl, Stan, custom)

## Deliverable
`notes/step07_inference_computation.md`