Address the Codex GPT-5.5 review of the standalone fake C++ gRPC Shard
worker. Four root protocol defects fixed:
- Fail closed before SessionOpen: a per-session `opened` flag gates
chunk/decode so no activation bypasses lifecycle, cancellation, epoch
or flow-control state (terminal ERROR_CODE_INTERNAL), even when an
out-of-band Cancel created placeholder state.
- Strict flow-control negotiation: NegotiateFlow takes the strictest of
peer-vs-worker bounds (mirrors codec.negotiate_flow_control) and the
negotiated per-session max_chunk_bytes is enforced on every bundle
instead of trusting the peer proposal.
- In-stream ReleaseSignal now erases session state immediately.
- SessionOpen rejects incompatible schema, fingerprint, and shard-range
identity and reports the worker's own served fingerprint rather than
echoing the caller.
Adds 9 regression tests (worker suite 18 -> 27). Real gates on the
rebuilt pinned-gRPC binary: cmake build exit 0; ctest 2/2; worker
pytest 27 passed; harness+protocol 63 passed; compileall 0; diff --check
clean; ldd/nm show 0 llama/ggml linkage. DGR-033 passes -> true.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
