LangFlow adapter audit

The adapter targets the read-only LangFlow checkout at commit a712b08570c56c787d6ef24f8e906a2dcdf768f5. It does not patch or copy model code. The supported registry cells are LangFlow/LM1B and LangFlow/OWT; each cell binds its own official Hugging Face checkpoint and tokenizer contract.

The pinned release's public upstreams/langflow/inference.py hard-codes its bundled config directory, which is not dataset-safe for the LM1B and OWT checkpoint pair. The adapter therefore enters through adapters/sample_langflow.py: it imports the pinned upstream LangFlow model code, loads LangFlowConfig from the selected checkpoint directory, and keeps the upstream underscore-style argparse contract. The exact mapping is:

--checkpoint: immutable canonical checkpoints/official/langflow/<dataset>/model.safetensors
--num_samples: requested sample count, with upstream remainder batching
--num_steps: requested many-step grid value
--seq_length: canonical dataset length, 128 for LM1B and 1024 for OWT
--seed: request seed
--output: canonical upstream_samples.txt in the run directory
--tokenizer: canonical dataset tokenizer from artifacts/data.yaml

The shared dlb.adapters.capture process observes the token tensor returned by the real LangFlow.generate_samples method and the text returned by the real tokenizer. It writes upstream_token_ids.json using dlb-upstream-token-capture-v1; conversion does not parse the upstream text file's human-oriented sample delimiters. Before upstream execution, the wrapper cross-checks the dataset tokenizer and revision in artifacts/data.yaml against data/manifests/downloads.json, requires that manifest's immutable local snapshot directory, and replaces the upstream movable tokenizer request with that path plus local_files_only=True under Hugging Face offline mode. There is no network or moving-revision fallback. Conversion requires exactly the requested number of fixed-length token rows and validates Task 7's runner-resolved checkpoint digest, lock ID, selection, and continuous_langflow family before reading the capture.

The upstream does not report per-sample latency. Canonical records therefore use schema-permitted 0.0 only as an excluded sentinel; conversion metadata states unavailable_excluded_sentinel and exclude_from_latency: true.