Enhance video library management in PLib by introducing folder change tracking and improving video item metadata handling. Update IVideoRepository to include a method for loading video items with labels. Revise VideoPlayerViewModel to manage playback progress and integrate new UI elements for displaying watched status and resume options. Update MainWindowViewModel to observe folder changes for automatic rescanning. Enhance README.md to document these new features and usage instructions.

src/PLib.Infrastructure/Persistence/DesignTimeDbContextFactory.cs

@@ -0,0 +1,16 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Design;
+
+namespace PLib.Infrastructure.Persistence;
+
+/// <summary>
+/// Used only by <c>dotnet ef</c> when it needs a context without running the application.
+/// The connection string is irrelevant for generating migrations — nothing connects.
+/// </summary>
+public sealed class DesignTimeDbContextFactory : IDesignTimeDbContextFactory<LibraryDbContext>
+{
+    public LibraryDbContext CreateDbContext(string[] args) =>
+        new(new DbContextOptionsBuilder<LibraryDbContext>()
+            .UseSqlite("Data Source=design-time.db")
+            .Options);
+}