feat(sms): bring-your-own-provider — cafés use their own SMS account

The platform no longer sells SMS. Each café saves its OWN Kavenegar API
key + sender line (new Cafes columns + migration) and campaigns are sent
and billed through that account.

Backend:
- GET/PUT /sms/settings (Manager/Owner; key echoed masked, verified
  against the provider before saving)
- campaign + balance use the café's credentials; SMS_NOT_CONFIGURED
  error when missing; plan-tier SMS gating removed everywhere
  (PlanLimitChecker, SmsMarketingService, billing status)
- platform Kavenegar config stays ONLY for login OTPs (env/DB)
- design-time DbContext factory so `dotnet ef migrations add` works
  without booting the host

Dashboard:
- SMS screen: provider-settings card, not-configured callout, campaign
  form disabled until configured; quota bar removed (usage stays as info)
- subscription screen + plan comparison no longer show SMS limits

Admin panel:
- Kavenegar/SMS section removed from integrations (request field now
  optional; stored OTP config untouched)
- SMS limit field removed from the plan editor
- nav label "درگاه و پیامک" → "درگاه پرداخت و AI"

fa/en/ar translations. 86 tests pass; all tsc clean.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/Meezi.Infrastructure/Data/DesignTimeDbContextFactory.cs

@@ -0,0 +1,25 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Design;
+
+namespace Meezi.Infrastructure.Data;
+
+/// <summary>
+/// Design-time factory so `dotnet ef migrations add` works without booting the
+/// full API host (which needs Redis etc.). Generating a migration never connects
+/// to the database, so a placeholder connection string is fine; for commands that
+/// DO connect (database update), set MEEZI_DESIGNTIME_DB to a real string.
+/// </summary>
+public class DesignTimeDbContextFactory : IDesignTimeDbContextFactory<AppDbContext>
+{
+    public AppDbContext CreateDbContext(string[] args)
+    {
+        var conn = Environment.GetEnvironmentVariable("MEEZI_DESIGNTIME_DB")
+                   ?? "Host=localhost;Database=meezi;Username=meezi;Password=design-time-only";
+
+        var options = new DbContextOptionsBuilder<AppDbContext>()
+            .UseNpgsql(conn)
+            .Options;
+
+        return new AppDbContext(options);
+    }
+}

src/Meezi.Infrastructure/Data/Migrations/20260612051150_AddCafeSmsCredentials.cs

@@ -0,0 +1,38 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace Meezi.Infrastructure.Data.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddCafeSmsCredentials : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<string>(
+                name: "SmsApiKey",
+                table: "Cafes",
+                type: "text",
+                nullable: true);
+
+            migrationBuilder.AddColumn<string>(
+                name: "SmsSenderNumber",
+                table: "Cafes",
+                type: "text",
+                nullable: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "SmsApiKey",
+                table: "Cafes");
+
+            migrationBuilder.DropColumn(
+                name: "SmsSenderNumber",
+                table: "Cafes");
+        }
+    }
+}

src/Meezi.Infrastructure/Data/Migrations/AppDbContextModelSnapshot.cs

@@ -370,6 +370,12 @@ namespace Meezi.Infrastructure.Data.Migrations
                         .HasMaxLength(100)
                         .HasColumnType("character varying(100)");
 
+                    b.Property<string>("SmsApiKey")
+                        .HasColumnType("text");
+
+                    b.Property<string>("SmsSenderNumber")
+                        .HasColumnType("text");
+
                     b.Property<string>("SnappfoodVendorId")
                         .HasMaxLength(100)
                         .HasColumnType("character varying(100)");

src/Meezi.Infrastructure/ExternalServices/KavenegarSmsService.cs

@@ -123,6 +123,12 @@ public class KavenegarSmsService : ISmsService
     {
         var (apiKey, _, _) = await GetConfigAsync(cancellationToken);
         if (string.IsNullOrWhiteSpace(apiKey)) return null;
+        return await GetAccountInfoAsync(apiKey, cancellationToken);
+    }
+
+    public async Task<KavenegarAccountInfo?> GetAccountInfoAsync(string apiKey, CancellationToken cancellationToken = default)
+    {
+        if (string.IsNullOrWhiteSpace(apiKey)) return null;
 
         try
         {
@@ -140,6 +146,46 @@ public class KavenegarSmsService : ISmsService
         }
     }
 
+    /// <summary>
+    /// Bulk send with a café's OWN credentials — marketing SMS is bring-your-own-provider,
+    /// the platform account is only used for OTP and system messages.
+    /// </summary>
+    public async Task<BulkSendResult> SendBulkWithCredentialsAsync(
+        string apiKey,
+        string senderNumber,
+        IReadOnlyList<string> phones,
+        string message,
+        CancellationToken cancellationToken = default)
+    {
+        if (phones.Count == 0) return new BulkSendResult(0, 0);
+        if (string.IsNullOrWhiteSpace(apiKey))
+            return new BulkSendResult(0, phones.Count);
+
+        int sent = 0, failed = 0;
+
+        foreach (var batch in phones.Chunk(MaxBatchSize))
+        {
+            try
+            {
+                var receptors = batch.Select(NormalizePhone).ToList();
+                await RunSdkAsync(apiKey, api =>
+                {
+                    api.Send(senderNumber, receptors, message);
+                }, "BulkSendOwn");
+
+                sent += batch.Length;
+                _logger.LogInformation("Kavenegar own-credentials bulk batch: {Count} sent", batch.Length);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogWarning(ex, "Kavenegar own-credentials bulk batch failed ({Count} recipients)", batch.Length);
+                failed += batch.Length;
+            }
+        }
+
+        return new BulkSendResult(sent, failed);
+    }
+
     // ── SDK runner ────────────────────────────────────────────────────────────
 
     /// <summary>