feat: integrate PYMS payment gateway, add blog/sitepage/image services, local file manager

Payment Gateway:
- Add PYMSPaymentService: IPaymentGatewayService via gRPC to PYMS microservice
- Add ZarinPalPaymentService: direct ZarinPal integration (backup)
- Register 'pyms' payment provider in DI ConfigureServices
- Add PYMS proto files (pyms_transaction.proto, pyms_public_messages.proto)
- Fix VerifyDiscountWalletCharge: pass 'OK' as status instead of Authority
- Update appsettings: PaymentProvider=pyms, sandbox mode, merchant ID

Blog System:
- Add BlogCategory, BlogPost, BlogPostImage entities and CQRS
- Add proto files and gRPC services for blog management
- Add Mapster profiles for blog responses

Content Management:
- Add SitePage entity and CQRS for static pages
- Add proto and gRPC service for site pages

Image/File Management:
- Add LocalFileManager with disk storage + base64 serving + FMS fallback
- Add ImagePathResolverInterceptor for gRPC responses
- Add ImageResolverService for explicit image resolution
- Add UploadsController for public file serving with FMS fallback
- Add PaymentCallbackController for discount order payment callbacks

Database:
- Add blog and content entity migrations
- Remove ImagePath MaxLength constraints
- Remove old FileManagementService (replaced by LocalFileManager)

src/CMSMicroservice.Application/UserCQ/Commands/AcceptContract/AcceptContractCommandHandler.cs

@@ -24,15 +24,9 @@ public class AcceptContractCommandHandler : IRequestHandler<AcceptContractComman
 
     public async Task<AcceptContractResponseDto> Handle(AcceptContractCommand request, CancellationToken cancellationToken)
     {
-        // Verify OTP first
-        var otpToken = await _context.OtpTokens
-            .Where(x => x.Mobile == _currentUserService.Username && x.Purpose == "signContract" && !x.IsUsed)
-            .OrderByDescending(x => x.Id)
-            .FirstOrDefaultAsync(cancellationToken);
-
-        var secret = _cfg["Otp:Secret"] ?? throw new InvalidOperationException("Otp:Secret not set");
-        if (otpToken == null || !otpToken.IsValid() || !_hashService.VerifyHmacSha256Hex(request.Code, otpToken.CodeHash, secret))
-            return new AcceptContractResponseDto { IsSuccess = false, Message = "کد تایید نامعتبر است" };
+        // پیدا کردن کاربر بر اساس UserId از توکن JWT
+        if (!long.TryParse(_currentUserService.UserId, out var userId))
+            return new AcceptContractResponseDto { IsSuccess = false, Message = "کاربر احراز هویت نشده است" };
 
         var user = await _context.Users
             .Include(u => u.UserContracts)
@@ -40,12 +34,22 @@ public class AcceptContractCommandHandler : IRequestHandler<AcceptContractComman
             .Include(u => u.UserRoles)
                 .ThenInclude(ur => ur.Role)
             .Include(u => u.ClubMembership)
-            .Where(x => x.Mobile == _currentUserService.Username)
+            .Where(x => x.Id == userId)
             .FirstOrDefaultAsync(cancellationToken);
 
         if (user == null)
             return new AcceptContractResponseDto { IsSuccess = false, Message = "کاربر یافت نشد" };
 
+        // جستجوی OTP بر اساس شماره موبایل کاربر (نه Username)
+        var otpToken = await _context.OtpTokens
+            .Where(x => x.Mobile == user.Mobile && x.Purpose == "signContract" && !x.IsUsed)
+            .OrderByDescending(x => x.Id)
+            .FirstOrDefaultAsync(cancellationToken);
+
+        var secret = _cfg["Otp:Secret"] ?? throw new InvalidOperationException("Otp:Secret not set");
+        if (otpToken == null || !otpToken.IsValid() || !_hashService.VerifyHmacSha256Hex(request.Code, otpToken.CodeHash, secret))
+            return new AcceptContractResponseDto { IsSuccess = false, Message = "کد تایید نامعتبر است" };
+
         // Create user contract
         var userContract = new UserContract
         {
@@ -62,6 +66,16 @@ public class AcceptContractCommandHandler : IRequestHandler<AcceptContractComman
         
         await _context.SaveChangesAsync(cancellationToken);
 
+        // بارگذاری مجدد کاربر با تمام روابط برای تولید JWT صحیح
+        user = await _context.Users
+            .Include(u => u.UserContracts)
+                .ThenInclude(uc => uc.Contract)
+            .Include(u => u.UserRoles)
+                .ThenInclude(ur => ur.Role)
+            .Include(u => u.ClubMembership)
+            .Where(x => x.Id == userId)
+            .FirstAsync(cancellationToken);
+
         // Generate JWT token with updated contract status
         var token = await _generateJwt.GenerateJwtToken(user);