Add transaction_screening_local template (rules + query on local DuckDB)

[cafzal]

What

A beginner, rules-based template that runs entirely on a local DuckDB database — no Snowflake account or Native App. It triages a transfer ledger: classifies structuring and large-sender accounts, flags suspects, and expands a one-hop investigation set across the transfer network via a relationship self-join.

It's the local-development counterpart to the Snowflake-backed templates — same ontology → rules → query workflow, on an engine you can run anywhere.

Reasoning

• Rules-based: is_structuring, is_large_sender, is_suspect (OR-chained), near_suspect (1-hop).
• Querying / relationship traversal: network aggregates and a suspect → counterparty self-join over a transfers_to relationship (the local way to answer connectivity, without the graph reasoner).

Files

v1/transaction_screening_local/
├── README.md
├── pyproject.toml            # relationalai==1.8.1
├── transaction_screening_local.py
└── data/transactions.csv     # transfer ledger with an embedded structuring ring

Also adds the index row to v1/README.md.

Verification

Runs end-to-end on relationalai==1.8.1 (in-memory DuckDB): network overview, per-account volume, suspects (C1001 + ring C2001–C2005), the ring visible in the self-join, and the expanded investigation set. py_compile + ruff clean.

Notes / open items (draft)

• Local DuckDB execution uses deploy mode (enable_model_deployment=True + model.auto_deploy=True), which the package currently flags as experimental — confirm the support stance with the engine team before merging.
• This is a new local-DuckDB template category (no Snowflake). Confirm portfolio fit; it's adjacent to fraud-detection (multi-reasoner, Snowflake) and commercial_underwriting (rules) but distinct.
• The graph reasoner is intentionally not used — it's not reliable on local DuckDB (details in rai-agent-evals PR #108).

[github-actions]

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