fix(data): address code review findings

- Fix sort order regression in GetByListIdAsync (was descending, should be ascending)
- Restore WAL mode pragma (was silently dropped in EF migration)
- Add existing-DB compatibility shim in MigrateAndConfigure (baselines InitialCreate
  migration for databases created by the old schema.sql)
- Remove dead AddDbContext/AddScoped registrations from Worker (only IDbContextFactory
  is used by singleton consumers)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/ClaudeDo.App/Program.cs

@@ -21,7 +21,8 @@ sealed class Program
 
         using (var scope = services.CreateScope())
         {
-            scope.ServiceProvider.GetRequiredService<ClaudeDoDbContext>().Database.Migrate();
+            ClaudeDoDbContext.MigrateAndConfigure(
+                scope.ServiceProvider.GetRequiredService<ClaudeDoDbContext>());
         }
 
         try

src/ClaudeDo.Data/ClaudeDoDbContext.cs

@@ -1,5 +1,7 @@
 using ClaudeDo.Data.Models;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage;
 
 namespace ClaudeDo.Data;
 
@@ -19,4 +21,44 @@ public class ClaudeDoDbContext : DbContext
     {
         modelBuilder.ApplyConfigurationsFromAssembly(typeof(ClaudeDoDbContext).Assembly);
     }
+
+    /// <summary>
+    /// Applies EF Core migrations and sets WAL mode. Safe for both fresh and existing databases.
+    /// Existing databases (created by the old schema.sql) have their tables but no
+    /// __EFMigrationsHistory — this method detects that case and baselines the initial
+    /// migration so EF skips re-creating tables that already exist.
+    /// </summary>
+    public static void MigrateAndConfigure(ClaudeDoDbContext db)
+    {
+        // If the 'lists' table exists but __EFMigrationsHistory does not,
+        // this is a pre-EF database. Baseline the InitialCreate migration.
+        var conn = db.Database.GetDbConnection();
+        conn.Open();
+        using (var cmd = conn.CreateCommand())
+        {
+            cmd.CommandText = "SELECT COUNT(*) FROM sqlite_master WHERE type='table' AND name='lists'";
+            var hasLists = Convert.ToInt64(cmd.ExecuteScalar()) > 0;
+
+            cmd.CommandText = "SELECT COUNT(*) FROM sqlite_master WHERE type='table' AND name='__EFMigrationsHistory'";
+            var hasHistory = Convert.ToInt64(cmd.ExecuteScalar()) > 0;
+
+            if (hasLists && !hasHistory)
+            {
+                // Create the history table and mark InitialCreate as applied.
+                cmd.CommandText = """
+                    CREATE TABLE "__EFMigrationsHistory" (
+                        "MigrationId" TEXT NOT NULL CONSTRAINT "PK___EFMigrationsHistory" PRIMARY KEY,
+                        "ProductVersion" TEXT NOT NULL
+                    );
+                    INSERT INTO "__EFMigrationsHistory" ("MigrationId", "ProductVersion")
+                    VALUES ('20260416064948_InitialCreate', '8.0.11');
+                    """;
+                cmd.ExecuteNonQuery();
+            }
+        }
+        conn.Close();
+
+        db.Database.Migrate();
+        db.Database.ExecuteSqlRaw("PRAGMA journal_mode=WAL");
+    }
 }

src/ClaudeDo.Data/Repositories/TaskRepository.cs

@@ -38,7 +38,7 @@ public sealed class TaskRepository
     {
         return await _context.Tasks
             .Where(t => t.ListId == listId)
-            .OrderByDescending(t => t.CreatedAt)
+            .OrderBy(t => t.CreatedAt)
             .ToListAsync(ct);
     }
 

src/ClaudeDo.Installer/Steps/InitDatabaseStep.cs

@@ -19,7 +19,7 @@ public sealed class InitDatabaseStep : IInstallStep
                 .UseSqlite($"Data Source={expandedPath}")
                 .Options;
             using var context = new ClaudeDoDbContext(options);
-            context.Database.Migrate();
+            ClaudeDoDbContext.MigrateAndConfigure(context);
 
             progress.Report("Schema applied successfully");
             return Task.FromResult(StepResult.Ok());

src/ClaudeDo.Worker/Program.cs

@@ -17,16 +17,8 @@ builder.Host.UseWindowsService(o => o.ServiceName = "ClaudeDoWorker");
 
 builder.Services.AddDbContextFactory<ClaudeDoDbContext>(opt =>
     opt.UseSqlite($"Data Source={cfg.DbPath}"));
-builder.Services.AddDbContext<ClaudeDoDbContext>(opt =>
-    opt.UseSqlite($"Data Source={cfg.DbPath}"));
 
 builder.Services.AddSingleton(cfg);
-builder.Services.AddScoped<TagRepository>();
-builder.Services.AddScoped<ListRepository>();
-builder.Services.AddScoped<TaskRepository>();
-builder.Services.AddScoped<SubtaskRepository>();
-builder.Services.AddScoped<WorktreeRepository>();
-builder.Services.AddScoped<TaskRunRepository>();
 builder.Services.AddHostedService<StaleTaskRecovery>();
 builder.Services.AddSignalR();
 
@@ -54,7 +46,8 @@ var app = builder.Build();
 
 using (var scope = app.Services.CreateScope())
 {
-    scope.ServiceProvider.GetRequiredService<ClaudeDoDbContext>().Database.Migrate();
+    ClaudeDoDbContext.MigrateAndConfigure(
+        scope.ServiceProvider.GetRequiredService<ClaudeDoDbContext>());
 }
 
 app.MapHub<WorkerHub>("/hub");