Make the treatment start date optional during prescription renewals

Affected users: Healthcare Professionals (Doctors and Nurses). Task affected: Renewing an existing medication in the MYLE EMR (Patient chart -> Medical note -> Prescriptions section).

Impact: High frequency and significant time loss. When a user renews a long-term prescription (e.g. a medication ongoing for 3 years), the system now defaults the start date to the current day. Because this field is currently mandatory, it prevents the user from quickly renewing the medication.

Current state: Users must manually dig through the patient's extensive history to find the original prescription and enter the exact historical start date before they can proceed with the renewal.