Do not auto-resolve refunds with zero or negative amounts

[royalpinto007]

Problem

The refund policy auto-resolves any amount where amount <= REFUND_AUTO_LIMIT. That includes 0, negative numbers, NaN, and potentially other invalid numeric values.

Relevant code: lib/policy.ts.

Expected behavior

Only finite refund amounts greater than zero and at or below the configured limit should be auto-resolved. Invalid or non-positive amounts should be escalated for human review.

Acceptance criteria

• Require the refund amount to be finite and greater than zero before auto-resolution.
• Escalate zero, negative, and non-finite amounts with a clear reason.
• Add focused policy tests for valid, zero, negative, and non-finite amounts.
• Preserve the current behavior for valid refunds above and below the limit.

[vsolano9]

I’m working on this. I’ll keep the change inside the policy boundary: prove the current zero/negative/non-finite behavior first, require a finite positive amount before automatic action, preserve valid below/at/above-limit decisions, and add focused policy tests with explicit escalation reasons.