blocker fix phase 4

server/src/Infrastructure/Baya.Infrastructure.Persistence/Configuration/BookingConfig/BookingRequestConfig.cs

@@ -1,4 +1,5 @@
 using Baya.Domain.Entities.Booking;
+using Baya.Infrastructure.Persistence.ValueConversion;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
 
@@ -16,7 +17,11 @@ internal sealed class BookingRequestConfig : IEntityTypeConfiguration<BookingReq
         builder.Property(r => r.CustomerNotes).HasMaxLength(1000);
         builder.Property(r => r.Status).HasMaxLength(50).IsRequired();
         builder.Property(r => r.NurseRejectionReason).HasMaxLength(500);
-        builder.Property(r => r.NurseResponseDeadlineAt).IsRequired();
+
+        // datetime2 loses Kind on read (comes back Unspecified); re-tag as Utc so JSON serialization keeps
+        // the trailing Z and clients don't misparse the deadline as local time (mvp/blocker-phases/04).
+        builder.Property(r => r.NurseResponseDeadlineAt).HasConversion(new UtcDateTimeConverter()).IsRequired();
+        builder.Property(r => r.PaymentDeadlineAt).HasConversion(new UtcDateTimeConverter());
 
         // Inbox lists read on (party, status), actionable-first; the two deadline indexes let the expiry
         // sweep select stale rows through a covering index instead of scanning the table.

server/src/Infrastructure/Baya.Infrastructure.Persistence/ValueConversion/UtcDateTimeConverter.cs

@@ -0,0 +1,14 @@
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+
+namespace Baya.Infrastructure.Persistence.ValueConversion;
+
+/// <summary>
+/// SQL Server's <c>datetime2</c> carries no timezone, so EF's provider returns <see cref="DateTimeKind.Unspecified"/>
+/// on read even though the value was always written as UTC — leaving it that way makes System.Text.Json omit the
+/// trailing <c>Z</c>, and clients then misparse the instant as local time. Re-tags the <see cref="DateTimeKind"/> as
+/// <see cref="DateTimeKind.Utc"/> on read; the value itself is never altered.
+/// </summary>
+internal sealed class UtcDateTimeConverter()
+    : ValueConverter<DateTime, DateTime>(
+        v => v,
+        v => DateTime.SpecifyKind(v, DateTimeKind.Utc));