Improve/Add Controls to Refund Processing

🔍 Problem Statement

Refund processing in Pelcro lacks flexibility — admins cannot issue partial refunds, refund to a different method, or add internal notes to refund records. This forces manual workarounds via the payment gateway and creates gaps in Pelcro's accounting records.

💡 User Story

As a Pelcro admin, I want improved refund controls (partial refunds, method selection, internal notes), so that I can handle refund scenarios directly in Pelcro without gateway workarounds.

🎯 Definition of Done (DoD)

A feature is done when:

✔️ Given a completed payment, when an admin initiates a refund, then they can specify a partial amount, select the refund destination, and add an internal note — and the refund is recorded accurately in Pelcro's accounting.