Allow SMS send with negative balance; only block switch stops sending.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/sms/sms.service.ts

@@ -1,8 +1,6 @@
 import {
   BadRequestException,
   ForbiddenException,
-  HttpException,
-  HttpStatus,
   Injectable,
   NotFoundException,
 } from '@nestjs/common';
@@ -256,11 +254,12 @@ export class SmsService {
     let reason: string | null = null;
     let allowed = true;
 
+    // Only the explicit block switch stops sending (parity with Hamkar/Khanegi panels).
+    // Negative / low balance is allowed; UI can still show balanceLevel as warning.
     if (account.isBlocked && !isAlert) {
       allowed = false;
       reason = 'blocked';
     } else if (!isAlert && account.balanceRials < estimatedCostRials) {
-      allowed = false;
       reason = 'insufficient_balance';
     }
 
@@ -306,18 +305,7 @@ export class SmsService {
 
       const costRials = parts * account.pricePerPartRials;
 
-      if (!isAlert && account.balanceRials < costRials) {
-        throw new HttpException(
-          {
-            message: 'موجودی کیف پول پیامک کافی نیست',
-            reason: 'insufficient_balance',
-            balanceRials: account.balanceRials,
-            costRials,
-          },
-          HttpStatus.PAYMENT_REQUIRED,
-        );
-      }
-
+      // Allow negative wallet (same as product panels): only isBlocked stops send/consume.
       const nextBalance = account.balanceRials - costRials;
 
       const updated = await tx.smsAccount.update({