feat(data): rename *.Services projects, lift TrackEntity onto BlazorBlocks data layer, regenerate initial Postgres migration

DeepDrftWeb.Services → DeepDrftData; DeepDrftContent.Services → DeepDrftContent.Data.
TrackEntity:BaseEntity, TrackRepository:Repository<>, TrackManager:Manager<>+ITrackService.
Drops DeepDrftModels PagingParameters/PagedResult in favour of Models.Common.* from BlazorBlocks.
InitialCreate migration captures full schema including is_deleted index.

DeepDrftModels/DTOs/TrackDto.cs

@@ -1,13 +1,21 @@
-namespace DeepDrftModels.DTOs;
+using Models.Models;
 
-public class TrackDto
+namespace DeepDrftModels.DTOs;
+
+// Inherits Id, CreatedAt, UpdatedAt from BaseModel (Cerebellum.BlazorBlocks.Models).
+// BlazorBlocks's Manager<> generic constraint requires `new()` on the model type, which
+// disqualifies `required` properties (the `new()` constraint and required members do not
+// compose). EntryKey/TrackName/Artist therefore drop `required` here — the TrackEntity
+// side remains required, and TrackConverter assigns every field on the round-trip so an
+// empty default is never observable in production code paths.
+public class TrackDto : BaseModel
 {
-    public long Id { get; set; }
-    public required string EntryKey { get; set; }
-    public required string TrackName { get; set; }
-    public required string Artist { get; set; }
+    public string EntryKey { get; set; } = string.Empty;
+    public string TrackName { get; set; } = string.Empty;
+    public string Artist { get; set; } = string.Empty;
     public string? Album { get; set; }
     public string? Genre { get; set; }
     public DateOnly? ReleaseDate { get; set; }
     public string? ImagePath { get; set; }
-}
+    public long? CreatedByUserId { get; set; }
+}

DeepDrftModels/DeepDrftModels.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
         <TargetFramework>net10.0</TargetFramework>
@@ -8,6 +8,7 @@
 
     <ItemGroup>
       <PackageReference Include="Cerebellum.NetBlocks" Version="10.3.30" />
+      <PackageReference Include="Cerebellum.BlazorBlocks.Models" Version="10.3.30" />
     </ItemGroup>
 
 </Project>

DeepDrftModels/Entities/TrackEntity.cs

@@ -1,8 +1,12 @@
-namespace DeepDrftModels.Entities;
+using Models.Entities;
 
-public class TrackEntity
+namespace DeepDrftModels.Entities;
+
+// Inherits Id, CreatedAt, UpdatedAt, IsDeleted from BaseEntity (Cerebellum.BlazorBlocks.Models).
+// BaseEntity ships the audit columns but does not declare IEntity itself, so subclasses
+// declare it explicitly to satisfy the generic constraints on Repository<>/Manager<>/etc.
+public class TrackEntity : BaseEntity, IEntity
 {
-    public long Id { get; set; }
     public required string EntryKey { get; set; }
     public required string TrackName { get; set; }
     public required string Artist { get; set; }
@@ -11,4 +15,4 @@ public class TrackEntity
     public DateOnly? ReleaseDate { get; set; }
     public string? ImagePath { get; set; }
     public long? CreatedByUserId { get; set; }
-}
+}

DeepDrftModels/Models/PagedResult.cs

@@ -1,35 +0,0 @@
-namespace DeepDrftModels.Models;
-
-public class PagedResult<T>
-{
-    public IEnumerable<T> Items { get; set; } = new List<T>();
-    public int TotalCount { get; set; }
-    public int Page { get; set; }
-    public int PageSize { get; set; }
-    public int TotalPages => PageSize > 0 ? (int)Math.Ceiling((double)TotalCount / PageSize) : 0;
-    public bool HasNextPage => Page < TotalPages;
-    public bool HasPreviousPage => Page > 1;
-
-    public PagedResult()
-    {
-    }
-
-    public static PagedResult<T> From<TOther>(PagedResult<TOther> other, IEnumerable<T> items)
-    {
-        return new PagedResult<T>()
-        {
-            Items = items.ToList(),
-            Page = other.Page,
-            PageSize = other.PageSize,
-            TotalCount = other.TotalCount,
-        };
-    }
-
-    public PagedResult(IEnumerable<T> items, int totalCount, int page, int pageSize)
-    {
-        Items = items.ToList();
-        TotalCount = totalCount;
-        Page = page;
-        PageSize = pageSize;
-    }
-} 

DeepDrftModels/Models/PagingParameters.cs

@@ -1,25 +0,0 @@
-using System.Linq.Expressions;
-
-namespace DeepDrftModels.Models;
-
-public class PagingParameters
-{
-    private const int _maxPageSize = 100;
-    private int _pageSize = 20;
-
-    public int Page { get; set; } = 1;
-    
-    public int PageSize
-    {
-        get => _pageSize;
-        set => _pageSize = value > _maxPageSize ? _maxPageSize : value;
-    }
-}
-
-public class PagingParameters<T> : PagingParameters
-{
-    public Expression<Func<T, object>>? OrderBy { get; set; }
-    public bool IsDescending { get; set; } = false;
-
-    public int Skip => (Page - 1) * PageSize;
-}