feat: extend contract checks DAG with customers task

[br413]

Renames DAG to dqo_contract_checks and adds customers validation task. Closes #3 prep.

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Note

Low Risk
Orchestration and documentation only; same CLI check path as before. Operators must adopt the new DAG id if anything referenced the old name.

Overview
Renames the scheduled Airflow DAG from dqo_orders_contract_checks to dqo_contract_checks and replaces the single orders-only task with two daily Bash tasks: orders first, then customers (run_orders_checks >> run_customers_checks).

Shared CLI flags (references, history DB, alert file, no console alerts) are factored into a CHECK_COMMAND constant; each task only adds contract and data paths. README, docs/scheduling.md, and tests/test_dags.py are updated for the new DAG id, file name dags/dqo_contract_checks.py, and the expectation of two tasks.

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Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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Orders failure skips customers checks

Medium Severity

run_orders_checks is wired upstream of run_customers_checks, and the CLI exits with a non-zero code when contract checks fail. Airflow then skips the customers task, so a failing orders run leaves the customers contract unvalidated for that schedule despite independent data and contracts.

 

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