File Created Date (#1434)

* Capture date when Kavita creates a MangaFile so we can show the date on the UI.

* On startup, exit early for migration directory if it's a fresh install and we have migrations to run but no settings stored yet.

* Blur summaries should apply when there isn't any read more collapsable

* Fixed custom theme files not loading.

* Cleaned up the logic for displaying the manga file date

API/DTOs/MangaFileDto.cs

@@ -1,4 +1,5 @@
-using API.Entities.Enums;
+using System;
+using API.Entities.Enums;
 
 namespace API.DTOs
 {
@@ -8,6 +9,7 @@ namespace API.DTOs
         public string FilePath { get; init; }
         public int Pages { get; init; }
         public MangaFormat Format { get; init; }
+        public DateTime Created { get; init; }
 
     }
 }