FileChooser: "percent - unopened - finished last" add "on-hold" handling

Squashed commit of the following:

commit dd618a4e42
Merge: 518b648c4 5414858b7
Author: SomeGuy <97603719+Commodore64user@users.noreply.github.com>
Date:   Tue Mar 12 23:23:59 2024 +0000

    Merge branch 'koreader:master' into master

commit 518b648c42
Author: SomeGuy <97603719+Commodore64user@users.noreply.github.com>
Date:   Thu Mar 7 10:59:16 2024 +0000

    Update filechooser.lua

    tidy-up

commit a6243e334e
Author: SomeGuy <97603719+Commodore64user@users.noreply.github.com>
Date:   Wed Mar 6 16:06:53 2024 +0000

    Update filechooser.lua

    adds instruction for files labeled "on hold" to sorting function

frontend/ui/widget/filechooser.lua

@@ -207,7 +207,7 @@ local FileChooser = Menu:extend{
             end,
         },
         percent_natural = {
-            -- sort 90% > 50% > 0% > unopened > 100% or finished
+            -- sort 90% > 50% > 0% or on hold > unopened > 100% or finished
             text = _("percent - unopened - finished last"),
             menu_order = 90,
             can_collate_mixed = false,
@@ -235,9 +235,11 @@ local FileChooser = Menu:extend{
                     local doc_settings = DocSettings:open(item.path)
                     local summary = doc_settings:readSetting("summary")
 
-                    -- books marked as "finished" should be considered the same as 100%
+                    -- books marked as "finished" or "on hold" should be considered the same as 100% and 0% respectively
                     if summary and summary.status == "complete" then
                         item.sort_percent = 1.0
+                    elseif summary and summary.status == "abandoned" then
+                        item.sort_percent = 0
                     end
 
                     percent_finished = doc_settings:readSetting("percent_finished")