[DeckEditor] Use CommanderSpellbook.com to estimate bracket if format is 'commander' (#6415)

* [DeckEditor] Use CommanderSpellbook.com to estimate bracket if format is 'commander'

Took 2 minutes

Took 16 minutes

* Convert json data holder to structs, rename variables, extract widget

- Extract bracket estimation UI from DeckEditorDeckDockWidget into a
  new CommanderBracketWidget
- Move CommanderSpellbook integration settings from CardsDisplaySettings
  to DeckEditorSettings (matching the settings refactor on master)
- Rename CommanderSpellbook integration variables to drop the redundant
  'DeckEditor' prefix

Took 4 minutes

# Commit time for manual adjustment:
# Took 6 minutes

# Commit time for manual adjustment:
# Took 8 minutes

---------

Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>

cockatrice/src/client/settings/cache_settings.h

@@ -28,6 +28,7 @@ class CardDatabaseSettings;
 class CardOverrideSettings;
 class CardsDisplaySettings;
 class ChatSettings;
+class CommanderBracketSettings;
 class DebugSettings;
 class DeckEditorSettings;
 class DownloadSettings;
@@ -83,6 +84,7 @@ private:
     VisualDeckStorageSettings *visualDeckStorageSettings;
     AppearanceSettings *appearanceSettings;
     NetworkSettings *networkSettings;
+    CommanderBracketSettings *commanderBracketSettings;
 
     QString themeName;
 
@@ -150,6 +152,10 @@ public:
     [[nodiscard]] VisualDeckStorageSettings &visualDeckStorage() const;
     [[nodiscard]] AppearanceSettings &appearance() const;
     [[nodiscard]] NetworkSettings &network() const;
+    [[nodiscard]] CommanderBracketSettings &commanderBrackets() const
+    {
+        return *commanderBracketSettings;
+    }
 
     [[nodiscard]] bool getIsPortableBuild() const
     {