test: verify scheduler CAS on PostgreSQL (AEG-V15-036)

Adds a lease-loss/reacquire integration rehearsal and fixes Dapper due-schedule materialization with an explicit row DTO. Evidence: PostgreSQL test 1/1 passed; TRX SHA256 49627FF0180034D2A7A1E4393448C73D337D918E7CE47EA9FC2BDB144FBBA833.

src/KArtSell.Modules.ModelOperations/Infrastructure/DapperModelScheduleRepository.cs

@@ -79,8 +79,20 @@ public sealed class DapperModelScheduleRepository(IDbConnectionFactory connectio
     public async Task<IReadOnlyList<DueModelOperation>> AcquireDueAsync(DateTimeOffset now, string leaseOwner, TimeSpan leaseDuration, int limit, CancellationToken cancellationToken)
     {
         await using var connection = await connectionFactory.OpenAsync(cancellationToken);
-        var items = await connection.QueryAsync<DueModelOperation>(new CommandDefinition(AcquireSql, new { Now = now, LeaseOwner = leaseOwner, LeaseUntil = now.Add(leaseDuration), Limit = limit }, cancellationToken: cancellationToken));
-        return items.AsList();
+        var rows = await connection.QueryAsync<DueScheduleRow>(new CommandDefinition(AcquireSql, new { Now = now, LeaseOwner = leaseOwner, LeaseUntil = now.Add(leaseDuration), Limit = limit }, cancellationToken: cancellationToken));
+        return rows.Select(row => new DueModelOperation(
+            row.ScheduleId,
+            row.OperationCode,
+            row.ScopeKey,
+            row.Cadence,
+            row.AutomationMode,
+            row.Queue,
+            row.IdempotencyKey,
+            row.ScheduleVersion,
+            row.DispatchRevision,
+            row.ScheduledFor,
+            row.CatchUpPolicy,
+            row.MaxCatchUp)).ToArray();
     }
 
     public async Task MarkDispatchedAsync(Guid scheduleId, string leaseOwner, int expectedDispatchRevision, string backgroundJobId, DateTimeOffset dispatchedAt, DateTimeOffset nextDueAt, CancellationToken cancellationToken)
@@ -102,4 +114,20 @@ public sealed class DapperModelScheduleRepository(IDbConnectionFactory connectio
         await using var connection = await connectionFactory.OpenAsync(cancellationToken);
         await connection.ExecuteAsync(new CommandDefinition(ReleaseSql, new { ScheduleId = scheduleId, LeaseOwner = leaseOwner, ExpectedDispatchRevision = expectedDispatchRevision, ReasonCode = reasonCode, ReleasedAt = releasedAt }, cancellationToken: cancellationToken));
     }
+
+    private sealed class DueScheduleRow
+    {
+        public Guid ScheduleId { get; init; }
+        public string OperationCode { get; init; } = string.Empty;
+        public string ScopeKey { get; init; } = string.Empty;
+        public string Cadence { get; init; } = string.Empty;
+        public string AutomationMode { get; init; } = string.Empty;
+        public string Queue { get; init; } = string.Empty;
+        public string IdempotencyKey { get; init; } = string.Empty;
+        public int ScheduleVersion { get; init; }
+        public int DispatchRevision { get; init; }
+        public DateTimeOffset ScheduledFor { get; init; }
+        public string CatchUpPolicy { get; init; } = string.Empty;
+        public int MaxCatchUp { get; init; }
+    }
 }