feat: Add core entities and history tables for network-club system

Core Entities:
- Add SystemConfiguration for dynamic config management
- Add ClubMembership, ClubFeature, UserClubFeature for club management
- Add NetworkWeeklyBalance for binary network tracking
- Add WeeklyCommissionPool, UserCommissionPayout for commission system

History Entities (Audit Trail):
- Add ClubMembershipHistory
- Add NetworkMembershipHistory
- Add CommissionPayoutHistory
- Add SystemConfigurationHistory

Updates to Existing Entities:
- User: Add NetworkParentId, LegPosition, and navigation properties
- UserWallet: Add NetworkBalance and DiscountBalance fields
- Products: Add IsClubExclusive and ClubDiscountPercent fields
- GlobalUsings: Add new namespaces for club/network/commission entities

src/CMSMicroservice.Domain/Entities/Configuration/SystemConfiguration.cs

@@ -0,0 +1,42 @@
+namespace CMSMicroservice.Domain.Entities.Configuration;
+
+/// <summary>
+/// تنظیمات پویای سیستم - قابل تغییر بدون Deployment
+/// </summary>
+public class SystemConfiguration : BaseAuditableEntity
+{
+    /// <summary>
+    /// محدوده تنظیمات (System, Network, Club, Commission)
+    /// </summary>
+    public ConfigurationScope Scope { get; set; }
+
+    /// <summary>
+    /// کلید تنظیم (مثلاً "MaxWeeklyBalancesPerUser")
+    /// </summary>
+    public string Key { get; set; }
+
+    /// <summary>
+    /// مقدار به‌صورت رشته (تفسیر در Application Layer)
+    /// </summary>
+    public string Value { get; set; }
+
+    /// <summary>
+    /// نوع داده برای Validation و UI (Int/Decimal/Bool/String/Json)
+    /// </summary>
+    public string? DataType { get; set; }
+
+    /// <summary>
+    /// توضیحات برای ادمین
+    /// </summary>
+    public string? Description { get; set; }
+
+    /// <summary>
+    /// فعال یا غیرفعال
+    /// </summary>
+    public bool IsActive { get; set; }
+
+    /// <summary>
+    /// SystemConfigurationHistory Collection Navigation Reference
+    /// </summary>
+    public virtual ICollection<SystemConfigurationHistory>? SystemConfigurationHistories { get; set; }
+}