feat(local): serverless local execution runtime (opensop-local)

[Chosen9115]

Serverless local execution for OpenSOP (opensop-local)

Adds a local runtime: run an OpenSOP process on-machine with no server — no Rails app, no daemon, no network. Reads a process definition, runs its steps in order, threads a JSON context between them, and writes an append-only on-disk receipt per step.

Why: today a process runs on the Rails runtime, and opensop-cli is a thin HTTP client to that server. This lets you run the same kind of process with just the CLI — for development, CI, air-gapped/edge environments, and lightweight agents that can't carry a Ruby runtime.

Dependencies: bash + jq. (Optional yq/PyYAML for .sop.yaml → JSON.)

What's in this PR (local/)

• bin/opensop-local — the runtime: run / list / runs / show / import-yaml.
• examples/greet.sop.json + examples/steps/build.sh — a minimal worked example.
• test/test.sh — golden test (passing): asserts 2 steps run, context threads, receipts are written, and no step-output leak.
• README.md — format, the step I/O contract, step-type matrix, audit format, design notes.

Model

• Process format: .sop.json (jq-native, zero extra deps), mirroring SPEC.md. import-yaml converts .sop.yaml.
• Step I/O contract: each step gets the accumulated context (process inputs + prior step outputs) on stdin and in $OSL_CONTEXT; its JSON stdout merges back under the step id (non-JSON → {stdout: …}).
• Step types (local): automated, shell, noop ✅ today. form/approval/llm/webhook/subprocess/wait are the roadmap for full SPEC parity (see README table).
• Receipts: $OPENSOP_LOCAL_HOME/runs/<id>/{manifest.json, audit.jsonl, context.json} — the local equivalent of the DB receipts, fully inspectable.

Notes for review

• Self-contained under local/; nothing else in the repo is touched.
• from: expression resolution (exact server parity) and local-aware runs/show/status in opensop-cli are noted as follow-ups.
• Battle-tested driving a real lightweight agent's daily procedures before extraction/genericization.

Draft, for review — please don't merge yet. @kuri — would love your eyes on the format/IO-contract and where this should live long-term (here vs opensop-cli).

🤖 Generated with Claude Code

[Chosen9115]

Moving this to the opensop-cli repo — it's a CLI runtime and belongs there. New PR to follow in Chosen9115/opensop-cli.