fix: Debug for BlobReader (n0-computer#1479)

## Description

Was missing a `Debug` impl.

## Notes & open questions

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## Change checklist

- [ ] Self-review.
- [ ] Documentation updates if relevant.
- [ ] Tests if relevant.

iroh/src/client.rs

@@ -141,9 +141,11 @@ where
 /// Data reader for a single blob.
 ///
 /// Implements [`AsyncRead`].
+#[derive(derive_more::Debug)]
 pub struct BlobReader {
     size: u64,
     is_complete: bool,
+    #[debug("StreamReader")]
     stream: tokio_util::io::StreamReader<BoxStream<'static, io::Result<Bytes>>, Bytes>,
 }
 impl BlobReader {