Add visual indentation guides for group separators in presets list

Author: robertpiosik

packages/ui/src/components/editor/panel/Presets/Presets.module.scss

@@ -28,18 +28,34 @@
 
       .presets__item__left {
         flex: 1;
+        position: relative;
         &::after {
           content: '';
           flex: 1;
           height: 1px;
           margin-left: 4px;
           background: linear-gradient(
             to right,
-            var(--cwc-border-color-dimmed),
+            var(--vscode-tree-inactiveIndentGuidesStroke),
             transparent
           );
         }
       }
+
+      &--ending {
+        .presets__item__left::before {
+          content: '';
+          position: absolute;
+          top: 0;
+          left: 26px;
+          width: 1px;
+          height: 6px;
+          background-color: var(--vscode-tree-inactiveIndentGuidesStroke);
+        }
+        .presets__item__left::after {
+          margin-bottom: 9px;
+        }
+      }
     }
 
     &--highlighted {

packages/ui/src/components/editor/panel/Presets/Presets.tsx

@@ -297,14 +297,24 @@ export const Presets: React.FC<Presets.Props> = (props) => {
               }}
               animation={150}
             >
-              {sortable_list.map((preset) => {
+              {sortable_list.map((preset, index) => {
                 if (!preset.chatbot && !preset.name) {
+                  const is_previous_in_group =
+                    index > 0 &&
+                    preset_indices_in_group.has(
+                      sortable_list[index - 1].original_index
+                    )
+
                   return (
                     <div
                       key={preset.id}
                       className={cn(
                         styles.presets__item,
-                        styles['presets__item--separator']
+                        styles['presets__item--separator'],
+                        {
+                          [styles['presets__item--separator--ending']]:
+                            is_previous_in_group
+                        }
                       )}
                     >
                       <div className={styles.presets__item__left}>