Possibly fix issues

After doing testing with a test project, re-organized code to new method
of storing, as well as ensure that all Endpoint lambda's are separated
out into functions.

Large commit, will be testing.

FreeTubeSync/Model/Subscription.cs

@@ -0,0 +1,11 @@
+using Microsoft.EntityFrameworkCore;
+
+namespace FreeTubeSync.Model;
+
+[Owned]
+public class Subscription
+{
+    public string id { get; set; } = string.Empty;
+    public string name { get; set; } = string.Empty;
+    public string? thumbnail { get; set; }
+}