feat(abgabe): Reservierungs-/Abgabe-Status (verfügbar/reserviert/abgegeben)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

GerbilManagerWebAPI/Models/SaleReservation.cs

@@ -0,0 +1,58 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace GerbilManagerWebAPI.Models
+{
+    /// <summary>
+    /// ABGABE-STATUS (RPRO3 abgeben_tb / abstat_tb): the pre-handover reservation/sale
+    /// pipeline for an animal — verfügbar (available) → reserviert (reserved) → abgegeben
+    /// (handed over). This is the *informal status* that precedes the legal sale contract
+    /// (SaleContract) — it does NOT replace it.
+    ///
+    /// Deliberately decoupled from the rest of the model (same pattern as Feedback):
+    /// GerbilId and ReservedForContactId are plain nullable Guid columns, NOT enforced
+    /// foreign keys, so the import re-ingest wipe (IngestResolvedService) can delete and
+    /// recreate gerbils/contacts without deleting or breaking reservation rows. The
+    /// captured GerbilName/ContactName keep the row human-readable after a wipe.
+    /// </summary>
+    public class SaleReservation
+    {
+        [Key]
+        public Guid Id { get; set; }
+
+        /// <summary>Loose reference (no FK) to the animal this status is about.</summary>
+        public Guid GerbilId { get; set; }
+
+        /// <summary>Captured animal name (survives an ingest wipe).</summary>
+        public string? GerbilName { get; set; }
+
+        /// <summary>
+        /// Status: "verfuegbar" | "reserviert" | "abgegeben". Plain string, no FK —
+        /// keeps the row decoupled and ingest-surviving.
+        /// </summary>
+        public string Status { get; set; } = "verfuegbar";
+
+        /// <summary>Loose reference (no FK) to the reserving/receiving contact (Interessent/Abnehmer), if any.</summary>
+        public Guid? ReservedForContactId { get; set; }
+
+        /// <summary>Captured contact name (survives an ingest wipe).</summary>
+        public string? ContactName { get; set; }
+
+        /// <summary>Planned hand-over appointment (RPRO3 abgeben_tb._TERMIN).</summary>
+        public DateTime? AppointmentDate { get; set; }
+
+        /// <summary>Agreed price (RPRO3 abstat_tb._PRICE).</summary>
+        public decimal? Price { get; set; }
+
+        /// <summary>Free-text note (RPRO3 _BEM).</summary>
+        public string? Note { get; set; }
+
+        /// <summary>When the animal was actually handed over (RPRO3 abstat_tb._AM); null until "abgegeben".</summary>
+        public DateTime? HandedOverDate { get; set; }
+
+        /// <summary>Server-side creation time.</summary>
+        public DateTimeOffset CreatedAt { get; set; }
+
+        /// <summary>Server-side last-update time.</summary>
+        public DateTimeOffset UpdatedAt { get; set; }
+    }
+}