feat: demo mode with SQLite and seed tasks

Data/FocusContext.cs

@@ -26,5 +26,15 @@ public class FocusContext : DbContext
             entity.Property(e => e.CreatedAt).IsRequired();
             entity.Property(e => e.UpdatedAt).IsRequired();
         });
+
+        // Demo-Tasks fuer lokalen Test
+        var now = DateTime.UtcNow;
+        modelBuilder.Entity<FocusTask>().HasData(
+            new FocusTask { Id = 1, Title = "Projektstruktur klären", Description = "README, AGENTS.md, Lizenz", Order = 1, CreatedAt = now, UpdatedAt = now },
+            new FocusTask { Id = 2, Title = "API finalisieren", Description = "Health Endpoint, Validierung", Order = 2, CreatedAt = now, UpdatedAt = now },
+            new FocusTask { Id = 3, Title = "Frontend polishieren", Description = "CSS, Responsive, Tests", Order = 3, CreatedAt = now, UpdatedAt = now },
+            new FocusTask { Id = 4, Title = "Docker Setup prüfen", Description = "Healthcheck, CI/CD", Order = 4, CreatedAt = now, UpdatedAt = now },
+            new FocusTask { Id = 5, Title = "Doku vervollständigen", Description = "API Docs, Deployment Guide", Order = 5, CreatedAt = now, UpdatedAt = now }
+        );
     }
 }

FocusApp.csproj

@@ -12,6 +12,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="9.0.8" />
     <PackageReference Include="Pomelo.EntityFrameworkCore.MySql" Version="9.0.0" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="10.2.3" />
   </ItemGroup>

Program.cs

@@ -8,25 +8,39 @@ var builder = WebApplication.CreateBuilder(args);
 
 builder.Logging.AddFilter("Microsoft.AspNetCore.HttpLogging", LogLevel.Information);
 
-// Connection-String aus ENV-Variablen aufbauen (appsettings.json ist Fallback)
-static string BuildConnectionString(IConfiguration config)
+// Datenbank: MariaDB oder SQLite (Demo-Modus)
+static void ConfigureDatabase(IConfiguration config, IServiceCollection services)
 {
-    return $"Server={config["DB_HOST"] ?? "localhost"};" +
+    var dbHost = config["DB_HOST"];
+
+    if (!string.IsNullOrEmpty(dbHost))
+    {
+        // Produktion: MariaDB
+        var connectionString = $"Server={dbHost};" +
                                $"Port={config["DB_PORT"] ?? "3306"};" +
                                $"Database={config["DB_NAME"] ?? "focusapp"};" +
                                $"User={config["DB_USER"] ?? "focusapp"};" +
                                $"Password={config["DB_PASSWORD"] ?? "change-password"}";
-}
 
-var connectionString = BuildConnectionString(builder.Configuration);
-
-// Add services
-builder.Services.AddDbContext<FocusContext>(options =>
+        services.AddDbContext<FocusContext>(options =>
             options.UseMySql(
                 connectionString,
                 ServerVersion.AutoDetect(connectionString)
             )
-);
+        );
+        Console.WriteLine("Using MariaDB database");
+    }
+    else
+    {
+        // Demo-Modus: SQLite
+        services.AddDbContext<FocusContext>(options =>
+            options.UseSqlite("Data Source=focusapp-demo.db")
+        );
+        Console.WriteLine("Using SQLite database (demo mode)");
+    }
+}
+
+ConfigureDatabase(builder.Configuration, builder.Services);
 
 builder.Services.AddCors(options =>
 {