feat: link deposits to bill payment

apps/server/src/deposits/deposits.controller.ts

@@ -170,7 +170,7 @@ export class DepositsController {
       action: '退还押金',
       targetId: +id,
       targetType: 'deposit',
-      detail: `退还¥${result.refundAmount}, 扣除¥${result.deductionAmount}`,
+      detail: `退还全部可用押金 ¥${result.refundAmount}`,
       ipAddress,
       userAgent,
     });
@@ -182,7 +182,7 @@ export class DepositsController {
           recipientIds: [student.userId],
           type: 'deposit_refunded',
           title: '押金已退还',
-          content: `您的押金已退还,退还¥${result.refundAmount},扣除¥${result.deductionAmount}`,
+          content: `您的剩余押金已全部退还,金额: ¥${result.refundAmount}`,
         });
       }
     } catch (_) { /* don't block response */ }