Removed support contact messages from:
- No refund address scenario emails
- Both text and HTML email templates
This is consistent with the policy that no support is offered for refunds.
Enhanced the refund email system to properly notify users when their
cryptocurrency refunds cannot be processed due to being economically
unviable (too small to cover network transaction fees).
Changes:
- Updated send_refund_email() to differentiate between "no refund address"
and "economically unviable" scenarios with appropriate messaging
- Added email notifications in crypto watcher for all NOT_REFUNDED status
transitions due to economic viability:
* Duplicate payment processing (line ~1770)
* Expired payment processing (line ~2145)
* Underpayment processing (line ~2905)
* Passive monitoring refund retries (line ~3280)
- Added proper error handling for email sending to prevent disruption
- All economically unviable refund tests pass with no regressions
Users now receive clear explanations when refunds are too small to send
rather than being left without notification.
