fix: honor table search q param on users and related lists

Dashboard sends q, but users/classes/payments ignored it; accept q/search and normalize Persian digits.

components/classes/classService.js

@@ -4,7 +4,7 @@
 const Class = require('./classModel');
 const User = require('../users/userModel');
 const AppError = require('../../utils/AppError');
-const { calculateMeta } = require('../../utils/pagination');
+const { calculateMeta, escapeRegex, getSearchTerm } = require('../../utils/pagination');
 const { sendClassRegisteredSms } = require('../../utils/senders/smsMessages');
 const logger = require('../../utils/logger');
 
@@ -17,6 +17,11 @@ const getAll = async (query) => {
   if (query.courseId) filter.course = query.courseId;
   if (query.isActive !== undefined) filter.isActive = query.isActive === 'true';
 
+  const searchTerm = getSearchTerm(query);
+  if (searchTerm) {
+    filter.name = new RegExp(escapeRegex(searchTerm), 'i');
+  }
+
   const [items, total] = await Promise.all([
     Class.find(filter)
       .select('name course professor students capacity tuitionFee startDate endDate isActive adminNotes createdAt updatedAt')