from_pretrained() now warms up the common per-request variants with dummy inputs (device and host), so the first real call is within about 10% of later calls (independently verified in fresh processes; outputs bit-identical; steady-state latency unchanged). Adds model.warmup(...) for other variants, verbose=False by default, and documents the [server,test] extras and repo-root paths. tt-model.yaml and SERVING.md are unchanged.
