serialize request in sender (#53)

## 📝 Summary

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## ⛱ Motivation and Context

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## 📚 References

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## ✅ I have run these commands

* [ ] `make lint`
* [ ] `make test`
* [ ] `go mod tidy`

Author: dvush

proxy/sender_proxy.go

@@ -188,6 +188,11 @@ func (prx *SenderProxy) HandleParsedRequest(ctx context.Context, parsedRequest P
 	parsedRequest.systemEndpoint = false
 	prx.Log.Debug("Received request", slog.String("method", parsedRequest.method))
 
+	err := SerializeParsedRequestForSharing(&parsedRequest, prx.OrderflowSigner)
+	if err != nil {
+		prx.Log.Warn("Failed to serialize request for sharing", slog.Any("error", err))
+	}
+
 	select {
 	case <-ctx.Done():
 	case prx.shareQueue <- &parsedRequest: