Add switch to display Podcast image instead of Episode image

Closes #46

src/qml/FeedDetailsPage.qml

@@ -98,6 +98,7 @@ Kirigami.ScrollablePage {
         model: page.feed.entries ? page.feed.entries : emptyListModel
         delegate: GenericEntryDelegate {
             listViewObject: entryList
+            showFeedImage: false
         }
 
         header: ColumnLayout {

src/qml/GenericEntryDelegate.qml

@@ -26,6 +26,7 @@ AddonDelegates.RoundedItemDelegate {
 
     property bool isQueue: false
     property bool isDownloads: false
+    property bool showFeedImage: !SettingsManager.showEpisodeImage
     property QtObject listViewObject: undefined
     property bool selected: false
     property int row: model ? model.row : -1
@@ -195,7 +196,7 @@ AddonDelegates.RoundedItemDelegate {
 
         ImageWithFallback {
             id: img
-            imageSource: entry ? entry.cachedImage : "no-image"
+            imageSource: entry ? ( showFeedImage ? entry.feed.cachedImage : entry.cachedImage ) : "no-image"
             property int size: Kirigami.Units.gridUnit * 3
             Layout.preferredHeight: size
             Layout.preferredWidth: size

src/qml/Settings/AppearanceSettingsPage.qml

@@ -53,6 +53,19 @@ FormCard.FormCardPage {
                 SettingsManager.save();
             }
         }
+
+        FormCard.FormDelegateSeparator {}
+
+        FormCard.FormCheckDelegate {
+            id: showEpisodeImage
+            text: i18nc("@option:check", "Show episode image instead of podcast image in lists")
+            checked: SettingsManager.showEpisodeImage
+            onToggled: {
+                SettingsManager.showEpisodeImage = checked;
+                SettingsManager.save();
+            }
+        }
+
     }
 
     FormCard.FormHeader {

src/settingsmanager.kcfg

@@ -35,6 +35,10 @@
             <label>Always show the title of podcast feeds in subscription view</label>
             <default>false</default>
         </entry>
+        <entry name="showEpisodeImage" type="Bool">
+            <label>Show the image of the episode rather than the general podcast image</label>
+            <default>true</default>
+        </entry>
         <entry name="prioritizeStreaming" type="Bool">
             <label>Show streaming button instead of download button</label>
             <default>false</default>