`check_batch_consistency` is fully built but never wired to any entry point

[dinahmaccodes]

Tier: Medium
Description: consistency::check_batch_consistency (consistency.rs:131-174) is only called from test_consistency.rs. Closed issue #233's acceptance criteria explicitly required "implement batch consistency verification" and "add admin query to detect consistency violations" — only per-shipment scanning is exposed on-chain.
Files: contracts/shipment/src/consistency.rs:131-174, contracts/shipment/src/lib.rs
Tasks:

• Expose check_batch_consistency as an admin-gated query entrypoint
  Acceptance Criteria:
• Admins can run the batch-group consistency check on a live contract, fulfilling [CONTRACT] Add cross-shipment state consistency verification framework #233's original acceptance criteria

[Salome-Agu]

@Salome-Agu has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello Maintainer, I can fix this issues

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[canicefavour]

@canicefavour has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I can expose check_batch_consistency as an admin-gated query entrypoint in the shipment contract, preserving the existing consistency logic while making batch-group violations observable on live contracts and adding focused authorization/consistency coverage.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @canicefavour to this issue.