Fix H2 bidi streaming deadlock for gRPC reflection#601
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InternalSend blocked on requestBodyTask after receiving response headers. For gRPC bidi streaming (e.g. server reflection), the client waits for the response before half-closing, creating a deadlock: the proxy can't forward the response until Send() returns, but the client won't finish sending until it sees the response. When ProcessResponse completes but the request body is still uploading, let the request body task continue in the background with a dedicated buffer and CTS so the orchestrator can forward the response immediately. Also adds a reflection-based grpcurl integration test that exercises this code path.
This was referenced Apr 13, 2026
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Summary
InternalSendwhere the proxy blocked onrequestBodyTaskafter receiving response headers, preventing the response from being forwarded to the clientProcessResponsecompletes but the request body is still uploading, the request body task now continues in the background with a dedicatedRsBufferand CTS, allowing the orchestrator to forward the response immediatelyList_Services_Reflection_Through_Proxyintegration test that runsgrpcurl -insecure grpcb.in:9001 list(server reflection, no proto files) through the proxy