Fix payment display and dashboard refresh functionality

- Fix 'paid in full for others' payments showing CHF 0.00 instead of actual amount
- Add time-based sorting to payments (date + createdAt) for proper chronological order
- Redirect to dashboard after adding payment instead of payments list
- Implement complete dashboard refresh after payment deletion via modal
- Fix dashboard component reactivity for single debtor view updates

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/lib/components/DebtBreakdown.svelte

@@ -43,6 +43,11 @@
       currency: 'CHF'
     }).format(amount);
   }
+
+  // Export refresh method for parent components to call
+  export async function refresh() {
+    await fetchDebtBreakdown();
+  }
 </script>
 
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