Land end-to-end canonical benchmark observability and a synthetic datastream-connectivity preflight across the orchestrator, chat, worker-node, and Python tinygrad worker, plus an xtask validator, so a 4-stage 7B pipeline run is fully diagnosable.
- benchmark_observability: expand stamp() with canonical producer fields (producer_component/instance_id/process_id/sequence, wall_clock_unix_ms, monotonic_ms, clock_source) and schema_version so every event shares one envelope shape
- orchestrator_app + bin/{mvp_chat,worker_node}: stamp OrchBootstrap/OrchPromptEvent/ChatProgress/NodeEvent/SamplerHealth with the canonical fields plus span_id/parent_span_id, and add a 4-phase synthetic datastream preflight (ProducerConfigured/Connected/SyntheticEventSent/Observed) plus an endpoint_config_snapshot event on each process
- apps/mvp-node/tinygrad_worker: add apply_canonical_envelope()/datastream_endpoint_snapshot() and emit_python_datastream_preflight() mirroring the Rust preflight, and enrich benchmark_stamp() with the same producer fields
- bin/worker_node: pass MVP_DATASTREAM_ENDPOINT_ID/MVP_BENCHMARK_PRODUCER_INSTANCE/MVP_IROH_ENDPOINT_ADDR_MASK/MVP_IROH_RELAY_MODE env to the spawned tinygrad worker so its stamps identify the stage
- bin/mvp_chat: add --pipeline-parallel as an alias for --pipeline-stages (with a duplicate-guard) and bump recursion_limit
- xtask: add a benchmark-observability validator (ValidatorFinding/BenchmarkValidation, validate_benchmark_observability, canonical-stamp and stage/edge checks, evidence + gap-report builders) with tests for missing python datastream connectivity, wrong run_id, and missing span_id
Signed-off-by: Zachery Aaron Shores-Chmielewski <zacheryasc@gmail.com>