feat(api): add returning_to_sender tracking status and new transfer statuses

[increase-releases]

Spec sync a3c78cac10e5975eabebfb290f14b814

API changes (additive / non-breaking):

• New returning_to_sender member on check-transfer physical-check tracking and physical-card shipment tracking categories.
• New transfer lifecycle status members across FedNow / Real-Time Payments / Swift / Card Push / Wire transfers (e.g. pending_submission, pending_submitting, pending_initiating, pending_creating).
• New physical-card/check tracking categories: in_transit, processed_for_delivery, delivered, delivery_issue, returned_to_sender.
• New / reworded fields and descriptions on ACH transfers (company descriptive date, company entry description), entities & beneficial owners (identification), lockbox addresses/recipients, inbound mail items, pending transactions, and simulations.
• configured_endpoints unchanged at 238; openapi_spec_hash ed21325b… → a3c78cac….

⚠️ Held for manual review

This sync also bundles non-spec changes:

• .github/workflows/ci.yml: adds a test job.
• pyproject.toml: narrows the published sdist — drops tests/, examples/, bin/, mypy.ini, noxfile.py (keeps src/ + top-level metadata). Release/packaging change.
• uv.lock: lockfile churn.

Per automerge policy a spec sync must not silently change how the repo builds or releases, so this PR was not auto-merged. The CI/build edits are additive (no existing build/test/lint job was removed) and match the intended fleet-wide CI hardening, but still warrant a human look before merge.