add-shape-types-to-torch-model

You are porting a PyTorch model to use pyrefly's tensor shape type system.

The methodology below is mandatory; how much you write down depends on the job. Each step has an artifact — an audit table, a per-local reveal_type dump, a typed-interface receipt, an assert_type count. Working through them in order is not optional: the next step's input is the previous step's output, and skipping a step means substituting reasoning for testing, which is the primary failure mode.

What varies is the deliverable: