Progress Overhaul + Profile Page and a LOT more! (#4262)

Co-authored-by: Amelia <77553571+Fesaa@users.noreply.github.com>
Co-authored-by: Robbie Davis <robbie@therobbiedavis.com>

API/DTOs/Progress/ReadingSessionDto.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Generic;
+
+namespace API.DTOs.Progress;
+
+public sealed record ReadingSessionDto
+{
+    public int Id { get; set; }
+    public DateTime StartTimeUtc { get; set; }
+    public DateTime? EndTimeUtc { get; set; }
+    public bool IsActive { get; set; } = true;
+    public IList<ReadingActivityDataDto> ActivityData { get; set; }
+
+    public int UserId { get; set; }
+    public string Username { get; set; }
+}