feat: Add Protobuf definitions for Network Membership service

- Introduced `networkmembership.proto` with RPC methods for retrieving user network tree, statistics, and position.
- Implemented HTTP annotations for gRPC transcoding in the service methods.
- Added support for Google API annotations in `annotations.proto` and `http.proto`.
- Created `ConfigureServices.cs` to register FluentValidation for the Protobuf services.
- Updated project file to include necessary dependencies for gRPC and Protobuf.

src/FrontOffice.BFF.Application/NetworkMembershipCQ/Queries/GetMyNetworkPosition/GetMyNetworkPositionQuery.cs

@@ -0,0 +1,3 @@
+namespace FrontOffice.BFF.Application.NetworkMembershipCQ.Queries.GetMyNetworkPosition;
+
+public record GetMyNetworkPositionQuery : IRequest<GetMyNetworkPositionResponseDto>;

src/FrontOffice.BFF.Application/NetworkMembershipCQ/Queries/GetMyNetworkPosition/GetMyNetworkPositionQueryHandler.cs

@@ -0,0 +1,44 @@
+using CMSMicroservice.Protobuf.Protos.NetworkMembership;
+
+namespace FrontOffice.BFF.Application.NetworkMembershipCQ.Queries.GetMyNetworkPosition;
+
+public class GetMyNetworkPositionQueryHandler : IRequestHandler<GetMyNetworkPositionQuery, GetMyNetworkPositionResponseDto>
+{
+    private readonly IApplicationContractContext _context;
+    private readonly ICurrentUserService _currentUserService;
+
+    public GetMyNetworkPositionQueryHandler(
+        IApplicationContractContext context, 
+        ICurrentUserService currentUserService)
+    {
+        _context = context;
+        _currentUserService = currentUserService;
+    }
+
+    public async Task<GetMyNetworkPositionResponseDto> Handle(GetMyNetworkPositionQuery request, CancellationToken cancellationToken)
+    {
+        var userId = _currentUserService.UserId ?? throw new UnauthorizedAccessException("User not authenticated");
+
+        var response = await _context.NetworkMemberships.GetUserNetworkAsync(
+            new GetUserNetworkRequest { UserId = userId },
+            cancellationToken: cancellationToken);
+
+        return new GetMyNetworkPositionResponseDto
+        {
+            UserId = response.UserId,
+            ParentId = response.ParentId ?? 0,
+            ParentName = response.ParentName ?? string.Empty,
+            Position = response.NetworkLeg switch
+            {
+                0 => "Left",
+                1 => "Right",
+                _ => "Root"
+            },
+            Level = response.NetworkLevel,
+            ReferralCode = response.ReferralCode ?? string.Empty,
+            JoinedAt = response.JoinedAt?.ToDateTime() ?? DateTime.UtcNow,
+            HasLeftChild = response.LeftChildId.HasValue,
+            HasRightChild = response.RightChildId.HasValue
+        };
+    }
+}

src/FrontOffice.BFF.Application/NetworkMembershipCQ/Queries/GetMyNetworkPosition/GetMyNetworkPositionResponseDto.cs

@@ -0,0 +1,49 @@
+namespace FrontOffice.BFF.Application.NetworkMembershipCQ.Queries.GetMyNetworkPosition;
+
+public class GetMyNetworkPositionResponseDto
+{
+    /// <summary>
+    /// شناسه کاربر
+    /// </summary>
+    public long UserId { get; set; }
+
+    /// <summary>
+    /// شناسه والد
+    /// </summary>
+    public long ParentId { get; set; }
+
+    /// <summary>
+    /// نام والد
+    /// </summary>
+    public string ParentName { get; set; } = string.Empty;
+
+    /// <summary>
+    /// موقعیت در درخت (Left/Right)
+    /// </summary>
+    public string Position { get; set; } = string.Empty;
+
+    /// <summary>
+    /// سطح در درخت
+    /// </summary>
+    public int Level { get; set; }
+
+    /// <summary>
+    /// کد معرف
+    /// </summary>
+    public string ReferralCode { get; set; } = string.Empty;
+
+    /// <summary>
+    /// تاریخ عضویت
+    /// </summary>
+    public DateTime JoinedAt { get; set; }
+
+    /// <summary>
+    /// آیا فرزند چپ دارد؟
+    /// </summary>
+    public bool HasLeftChild { get; set; }
+
+    /// <summary>
+    /// آیا فرزند راست دارد؟
+    /// </summary>
+    public bool HasRightChild { get; set; }
+}