Koenig - Fixed card deselection when cursor exits top of doc

refs https://github.com/TryGhost/Ghost/issues/9623
- add a `exitCursorAtTop` action to `{{koenig-editor}}` that will deselect any cards before calling the closure action
- check if the we're on a card section when pressing UP or LEFT so that the cursor being before/after the card doesn't trip up the logic

lib/koenig-editor/addon/components/koenig-editor.js

@@ -371,6 +371,14 @@ export default Component.extend({
     },
 
     actions: {
+        exitCursorAtTop() {
+            if (this.selectedCard) {
+                this.deselectCard(this.selectedCard);
+            }
+
+            this.cursorDidExitAtTop();
+        },
+
         toggleMarkup(markupTagName, postEditor) {
             (postEditor || this.editor).toggleMarkup(markupTagName);
         },

lib/koenig-editor/addon/options/key-commands.js

@@ -182,8 +182,8 @@ export const DEFAULT_KEY_COMMANDS = [{
         let {isCollapsed, head: {offset, section}} = editor.range;
         let prevSection = section.isListItem ? section.parent.prev : section.prev;
 
-        if (isCollapsed && offset === 0 && !prevSection) {
-            koenig.cursorDidExitAtTop();
+        if (isCollapsed && (offset === 0 || section.isCardSection) && !prevSection) {
+            koenig.send('exitCursorAtTop');
         }
 
         return false;
@@ -196,8 +196,8 @@ export const DEFAULT_KEY_COMMANDS = [{
         // trigger a closure action to indicate that the caret "left" the top of
         // the editor canvas if the caret is at the very beginning of the doc
         let prevSection = section.isListItem ? section.parent.prev : section.prev;
-        if (isCollapsed && offset === 0 && !prevSection) {
-            koenig.cursorDidExitAtTop();
+        if (isCollapsed && (offset === 0 || section.isCardSection) && !prevSection) {
+            koenig.send('exitCursorAtTop');
             return;
         }