Problem: Shift swaps currently process without checking against scheduling/shift rules. When a swap violates a rule, the system only surfaces it post-approval via the broken rule notification, requiring a manual reversal after the fact.

For customers operating under legal or regulatory scheduling constraints, this is a meaningful risk - agents don't always know the rules, and a swap that breaks labor law can't simply be undone cleanly. It also makes the swap feature feel redundant: customers either avoid using it or layer manual review on top, which defeats the self-service value.

Proposed solution: Run shift/scheduling rule validation before a swap is approved. If the proposed swap would violate a rule, block it and surface the reason to the requester - rather than letting it go through and flagging it after.