feat(rennmausakte): Datenherkunft/Nachverfolgung pro Rennmaus

Neuer „Datenherkunft"-Button in der Rennmausakte öffnet einen Dialog, der zeigt,
aus welchen Quellen der Eintrag erzeugt wurde: Quelldateien (Stammbäume +
Wurfchronik), Anzahl zusammengeführter Datensätze, Eltern-Herleitung
(Methode/Konfidenz) und Hinweise (z. B. „per manueller Entscheidung zugeordnet",
„Konflikt gelöst", „aus N Datensätzen zusammengeführt").

Import: build_provenance() in merge_and_resolve.py sammelt die Herkunft über alle
deduplizierten Datensätze und schreibt sie als Provenance-JSON je Tier in
resolved_import.json. Backend: Gerbil.Provenance (nullable text) + Migration
AddGerbilProvenance, gemappt im Ingest und im GerbilDto zurückgegeben. Frontend:
ProvenanceDialog + Typen + Strings.

Tests: Ingest-Round-trip (vorhanden/abwesend), e2e provenance.spec.ts.
dotnet(212)/vitest(129)/playwright/tsc/eslint grün.

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

GerbilManagerWebAPI/Dtos/ApiDtos.cs

@@ -32,7 +32,8 @@ namespace GerbilManagerWebAPI.Dtos
         bool? IsDeaf,
         bool IsResident,
         string? ProfilePhotoUrl,
-        bool IsCastrated);
+        bool IsCastrated,
+        string? Provenance);
 
     public record LitterDto(
         Guid Id,

GerbilManagerWebAPI/Endpoints/GerbilEndpoints.cs

@@ -137,6 +137,7 @@ namespace GerbilManagerWebAPI.Endpoints
             g.Id, g.Name, g.Gender, g.Status, g.LitterId, g.OriginContactId, g.ReceiverContactId,
             g.EnclosureId, g.ColorVarietyId, g.DateOfBirth, g.DateOfDeath, g.CauseOfDeath,
             g.GoHomeDate, g.Genotype, g.SpottingType, g.Notes, g.ImportSource, g.ExternalRef, g.OriginBreeder,
-            g.CharacterTraits, g.CharacterNote, g.IsDeaf, g.IsResident, profilePhotoUrl, g.IsCastrated);
+            g.CharacterTraits, g.CharacterNote, g.IsDeaf, g.IsResident, profilePhotoUrl, g.IsCastrated,
+            g.Provenance);
     }
 }

GerbilManagerWebAPI/Import/IngestResolvedService.cs

@@ -160,6 +160,7 @@ namespace GerbilManagerWebAPI.Import
                     ImportSource = g.ImportSource,
                     ExternalRef = g.ExternalRef,
                     RawImportData = g.RawImportData,
+                    Provenance = g.Provenance,
                     OriginBreeder = g.OriginBreeder,
                     NameSearch = g.NameSearch,
                     CharacterTraits = g.CharacterTraits,

GerbilManagerWebAPI/Migrations/20260622133758_AddGerbilProvenance.cs

@@ -0,0 +1,28 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace GerbilManagerWebAPI.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddGerbilProvenance : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<string>(
+                name: "Provenance",
+                table: "Gerbils",
+                type: "text",
+                nullable: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "Provenance",
+                table: "Gerbils");
+        }
+    }
+}

GerbilManagerWebAPI/Migrations/ApplicationContextModelSnapshot.cs

@@ -912,6 +912,9 @@ namespace GerbilManagerWebAPI.Migrations
                     b.Property<Guid?>("OriginContactId")
                         .HasColumnType("uuid");
 
+                    b.Property<string>("Provenance")
+                        .HasColumnType("text");
+
                     b.Property<string>("RawImportData")
                         .HasColumnType("text");
 

GerbilManagerWebAPI/Models/Gerbil.cs

@@ -49,6 +49,13 @@ namespace GerbilManagerWebAPI.Models
         public string? ImportSource { get; set; }
         public string? ExternalRef { get; set; }
 
+        /// <summary>Data-provenance / traceability for the import: a JSON object describing
+        /// WHICH source information produced this entry (sourceFiles, mergedRecordCount,
+        /// fromWurfchronik, parentMethod/parentConfidence, notes). Written by the Python
+        /// merge_and_resolve step and surfaced read-only in the Rennmausakte
+        /// ("Nachverfolgungsinformationen"). Null = manually-added animal / no import data.</summary>
+        public string? Provenance { get; set; }
+
         /// <summary>Raw import payload preserved verbatim (rawGenotype + unmappedTokens like
         /// the Uw locus / WFNZ markers) so nothing from the spreadsheets is lost. JSON text.</summary>
         public string? RawImportData { get; set; }