[feat] Improved stream handling

## Describe the feature

- [ ] Improve how stream errors are handled & how stream pipelines are created: https://nodejs.org/api/stream.html#streampipelinestreams-options
- [ ] Support various streams as responses (such as a `fetch` response stream and a body)

Start with the linked Node.js stream pipeline documentation, then inspect Koa's existing stream response handling and how response bodies are created. Done means improving stream error handling and pipeline creation while supporting fetch response streams and bodies as responses.

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