feat(api): .NET 10 multi-tenant REST API

Full backend implementation:
- Multi-tenant cafe/restaurant management (menus, orders, tables, staff)
- POS order flow with ZarinPal and Snappfood payment integration
- OTP authentication via Kavenegar SMS
- QR digital menu with public discover/finder endpoints
- Customer loyalty, coupons, CRM
- PostgreSQL via EF Core, Redis for caching/sessions
- Background jobs, webhook handlers
- Full migration history

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/Meezi.Core/Interfaces/IBranchContext.cs

@@ -0,0 +1,9 @@
+namespace Meezi.Core.Interfaces;
+
+/// <summary>Optional branch scope from JWT (staff terminal / POS session).</summary>
+public interface IBranchContext
+{
+    string? CafeId { get; }
+    string? BranchId { get; }
+    bool HasBranch { get; }
+}

src/Meezi.Core/Interfaces/IPlatformRuntimeConfig.cs

@@ -0,0 +1,8 @@
+namespace Meezi.Core.Interfaces;
+
+public interface IPlatformRuntimeConfig
+{
+    Task<string?> GetAsync(string key, CancellationToken cancellationToken = default);
+    Task<IReadOnlyDictionary<string, string>> GetByPrefixAsync(string prefix, CancellationToken cancellationToken = default);
+    void InvalidateCache();
+}

src/Meezi.Core/Interfaces/ISmsService.cs

@@ -0,0 +1,7 @@
+namespace Meezi.Core.Interfaces;
+
+public interface ISmsService
+{
+    Task SendOtpAsync(string phone, string otp, CancellationToken cancellationToken = default);
+    Task SendMessageAsync(string phone, string message, CancellationToken cancellationToken = default);
+}

src/Meezi.Core/Interfaces/ISnappPayGateway.cs

@@ -0,0 +1,18 @@
+namespace Meezi.Core.Interfaces;
+
+public record SnappPayInitResult(bool Success, string? PaymentToken, string? PaymentUrl, string? ErrorMessage);
+
+public record SnappPayVerifyResult(bool Success, string? RefId, string? ErrorMessage);
+
+public interface ISnappPayGateway
+{
+    Task<bool> IsEnabledAsync(CancellationToken cancellationToken = default);
+    Task<SnappPayInitResult> RequestPaymentAsync(
+        long amountRials,
+        string transactionId,
+        string returnUrl,
+        CancellationToken cancellationToken = default);
+    Task<SnappPayVerifyResult> VerifyAndSettleAsync(
+        string paymentToken,
+        CancellationToken cancellationToken = default);
+}

src/Meezi.Core/Interfaces/ISnappfoodClient.cs

@@ -0,0 +1,11 @@
+namespace Meezi.Core.Interfaces;
+
+public interface ISnappfoodClient
+{
+    Task AcknowledgeOrderAsync(string snappfoodOrderId, CancellationToken cancellationToken = default);
+    Task NotifyOrderDeliveredAsync(string snappfoodOrderId, CancellationToken cancellationToken = default);
+    Task NotifyOrderStatusAsync(
+        string snappfoodOrderId,
+        string status,
+        CancellationToken cancellationToken = default);
+}

src/Meezi.Core/Interfaces/ITap30Client.cs

@@ -0,0 +1,10 @@
+namespace Meezi.Core.Interfaces;
+
+public interface ITap30Client
+{
+    Task AcknowledgeOrderAsync(string tap30OrderId, CancellationToken cancellationToken = default);
+    Task NotifyOrderStatusAsync(
+        string tap30OrderId,
+        string status,
+        CancellationToken cancellationToken = default);
+}

src/Meezi.Core/Interfaces/ITaraPaymentGateway.cs

@@ -0,0 +1,18 @@
+namespace Meezi.Core.Interfaces;
+
+public record TaraInitResult(bool Success, string? TraceNumber, string? PaymentUrl, string? ErrorMessage);
+
+public record TaraVerifyResult(bool Success, string? RefId, string? ErrorMessage);
+
+public interface ITaraPaymentGateway
+{
+    Task<bool> IsEnabledAsync(CancellationToken cancellationToken = default);
+    Task<TaraInitResult> RequestPaymentAsync(
+        long amountRials,
+        string invoiceNumber,
+        string callbackUrl,
+        CancellationToken cancellationToken = default);
+    Task<TaraVerifyResult> VerifyPaymentAsync(
+        string traceNumber,
+        CancellationToken cancellationToken = default);
+}

src/Meezi.Core/Interfaces/ITarazTaxService.cs

@@ -0,0 +1,8 @@
+namespace Meezi.Core.Interfaces;
+
+public record TarazSubmitResult(bool Success, string? TrackingCode, string? Message);
+
+public interface ITarazTaxService
+{
+    Task<TarazSubmitResult> SubmitDailyInvoicesAsync(string cafeId, DateTime dateUtc, CancellationToken cancellationToken = default);
+}

src/Meezi.Core/Interfaces/ITenantContext.cs

@@ -0,0 +1,17 @@
+using Meezi.Core.Enums;
+
+namespace Meezi.Core.Interfaces;
+
+public interface ITenantContext
+{
+    string? UserId { get; }
+    string? CafeId { get; }
+    EmployeeRole? Role { get; }
+    PlanTier? PlanTier { get; }
+    string? Language { get; }
+    /// <summary>Active branch from JWT when employee is branch-scoped.</summary>
+    string? BranchId { get; }
+    bool IsSystemAdmin { get; }
+    bool IsAuthenticated { get; }
+    bool IsCafeOwner => Role == EmployeeRole.Owner;
+}

src/Meezi.Core/Interfaces/IWebsiteService.cs

@@ -0,0 +1,14 @@
+namespace Meezi.Core.Interfaces;
+
+public interface IWebsiteService
+{
+    Task<(IReadOnlyList<object> Posts, int Total)> GetPostsAsync(
+        string locale, int page, int limit, CancellationToken ct = default);
+    Task<object?> GetPostAsync(string slug, string locale, CancellationToken ct = default);
+    Task<IReadOnlyList<object>> GetCommentsAsync(string slug, CancellationToken ct = default);
+    Task<object> AddCommentAsync(string slug, string authorName, string? email,
+        string content, string? ip, CancellationToken ct = default);
+    Task<object> CreateDemoRequestAsync(string contactName, string businessName,
+        string phone, string? email, string branchCount, string? notes, string source,
+        CancellationToken ct = default);
+}

src/Meezi.Core/Interfaces/IZarinPalGateway.cs

@@ -0,0 +1,21 @@
+namespace Meezi.Core.Interfaces;
+
+public record ZarinPalRequestResult(bool Success, string? Authority, string? PaymentUrl, string? ErrorMessage);
+
+public record ZarinPalVerifyResult(bool Success, string? RefId, string? ErrorMessage);
+
+public interface IZarinPalGateway
+{
+    Task<bool> IsEnabledAsync(CancellationToken cancellationToken = default);
+
+    Task<ZarinPalRequestResult> RequestPaymentAsync(
+        long amountRials,
+        string description,
+        string callbackUrl,
+        CancellationToken cancellationToken = default);
+
+    Task<ZarinPalVerifyResult> VerifyPaymentAsync(
+        string authority,
+        long amountRials,
+        CancellationToken cancellationToken = default);
+}