parakeet marketplace package ships model files flat, breaking the official sample's model_dir

[staging-devin-ai-integration]

Summary

Installing the parakeet plugin from the marketplace lays the 4 model files flat into models/, but both the official sample and the just download-parakeet-models recipe expect them inside a models/sherpa-onnx-nemo-parakeet-tdt-0.6b-v3-int8/ subdirectory. As a result, an install→run of the official sample fails with Plugin failed to create instance.

This is a registry / model-packaging issue, not a code bug in the server or the sample.

Details

• samples/pipelines/oneshot/parakeet-stt.yml:27 sets model_dir: models/sherpa-onnx-nemo-parakeet-tdt-0.6b-v3-int8.
• just download-parakeet-models (justfile:810+) creates that same subdir and downloads the files into it.
• Every other ML plugin in the registry ships a *.tar.bz2 that extracts to a named directory; parakeet instead ships the model files flat.
• After a marketplace install, the files land directly in models/, so model_dir does not resolve and instance creation fails.

Repro

1. Install the parakeet plugin via the marketplace (POST /api/v0/marketplace/install).
2. Run samples/pipelines/oneshot/parakeet-stt.yml (oneshot POST /api/v1/process).
3. Observe Plugin failed to create instance.
4. Manually move the 4 files into models/sherpa-onnx-nemo-parakeet-tdt-0.6b-v3-int8/ → sample works.

Suggested fix

Repackage the parakeet model as a *.tar.bz2 (or *.tar.zst) that extracts to the sherpa-onnx-nemo-parakeet-tdt-0.6b-v3-int8/ directory, matching every other plugin and the model_dir the sample/recipe expect.

Context

Found while adding CI coverage for the official oneshot samples (#542). The sample YAML itself is correct, so no sample change was made; tracking the packaging fix here.