fix(prescription): allow verification when patient buys medicine outside

Closes #47 (closed)

Description

This merge request fixes an issue where patient medicine prescriptions could not be verified if the patient purchased medicines outside the in-house pharmacy system.

Previously, the verification logic depended on internal pharmacy purchase records, causing prescriptions to remain in a pending or unverified state when medicines were obtained externally. This created workflow interruptions and incorrect prescription status tracking.

The fix updates the verification flow to support prescriptions marked as medicines bought outside, ensuring that verification can proceed regardless of the purchase source while maintaining existing validation rules.

Checklist

• The bug has been reproduced and confirmed.
• A clear and concise fix has been implemented.
• New tests have been added to prevent regressions.
• Existing tests are passing.