Add option to automatically split tall downloaded images (#7029)

* Auto split long images to improve performance of reader

* Auto split long images to improve performance of reader - fixed the sorting

* Improved performance of splitting by getting rid of 1 extra loop

* Cleaned up code and moved the functionality to work during the downloading process (unsure how this affects download speed)

* Replaced the import .* with the actual used imports

* Fixes for Bugs discovered during my testing

* Fixed last split missing bug.

* Reordered the download progress to be updated before splitting instead of after to reflect more meaningful progress of download

* Reverted last commit since it had no effect

* Improved progress tracking when a download is paused then resumed.

* Implemented the recommended changes to enhance the feature.

* Apply suggestions from code review

Co-authored-by: arkon <arkon@users.noreply.github.com>

* Update app/src/main/res/values/strings.xml

Co-authored-by: arkon <arkon@users.noreply.github.com>

Co-authored-by: arkon <arkon@users.noreply.github.com>

app/src/main/java/eu/kanade/tachiyomi/data/preference/PreferencesHelper.kt

@@ -200,6 +200,8 @@ class PreferencesHelper(val context: Context) {
 
     fun saveChaptersAsCBZ() = flowPrefs.getBoolean("save_chapter_as_cbz", true)
 
+    fun splitTallImages() = flowPrefs.getBoolean("split_tall_images", false)
+
     fun folderPerManga() = prefs.getBoolean(Keys.folderPerManga, false)
 
     fun numberOfBackups() = flowPrefs.getInt("backup_slots", 2)