feat: normalize release-cardinal fields out of track into a Release entity (Phase 8 §8.0)

DeepDrftData/Data/Configurations/TrackConfiguration.cs

@@ -1,6 +1,5 @@
 using Data.Data.Configurations;
 using DeepDrftModels.Entities;
-using DeepDrftModels.Enums;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
 
@@ -31,45 +30,25 @@ public class TrackConfiguration : BaseEntityConfiguration<TrackEntity>
             .HasMaxLength(200)
             .HasColumnName("track_name");
 
-        builder.Property(e => e.Artist)
-            .IsRequired()
-            .HasMaxLength(200)
-            .HasColumnName("artist");
-
-        builder.Property(e => e.Album)
-            .HasMaxLength(200)
-            .HasColumnName("album");
-
-        builder.Property(e => e.Genre)
-            .HasMaxLength(100)
-            .HasColumnName("genre");
-
-        builder.Property(e => e.ReleaseDate)
-            .HasColumnName("release_date");
-
-        builder.Property(e => e.ImagePath)
-            .HasMaxLength(500)
-            .HasColumnName("image_path");
-
-        builder.Property(e => e.CreatedByUserId)
-            .HasColumnName("created_by_user_id");
-
         builder.Property(e => e.OriginalFileName)
             .HasMaxLength(500)
             .HasColumnName("original_file_name");
 
-        builder.Property(e => e.ReleaseType)
-            .IsRequired()
-            .HasConversion<string>()   // Store as readable string, not int ordinal
-            .HasMaxLength(20)
-            .HasColumnName("release_type")
-            .HasDefaultValue(ReleaseType.Single);
-
         builder.Property(e => e.TrackNumber)
             .IsRequired()
             .HasColumnName("track_number")
             .HasDefaultValue(1);
 
+        builder.Property(e => e.ReleaseId)
+            .HasColumnName("release_id");
+
+        // Nullable FK to the release-cardinal row. SetNull on delete: removing a release leaves its
+        // tracks intact as loose tracks rather than cascading them away.
+        builder.HasOne(e => e.Release)
+            .WithMany(r => r.Tracks)
+            .HasForeignKey(e => e.ReleaseId)
+            .OnDelete(DeleteBehavior.SetNull);
+
         // Names the is_deleted index explicitly. BaseEntityConfiguration.Configure already
         // calls HasIndex(e => e.IsDeleted); this adds HasDatabaseName so EF always uses
         // "IX_track_is_deleted" regardless of auto-naming conventions.