Fixup: Complete type guards and improve type safety in config-subtree component

Adds type guards for _source and _description properties to prevent runtime crashes when
accessing metadata on non-leaf config nodes. Also removes unused parameters and adds explicit
TypeScript type annotations for better type safety.

Author: denniskigen

packages/apps/esm-implementer-tools-app/src/configuration/interactive-editor/config-subtree.component.tsx

@@ -10,21 +10,21 @@ export interface ConfigSubtreeProps {
 }
 
 export function ConfigSubtree({ config, path = [] }: ConfigSubtreeProps) {
-  function setActiveItemDescriptionOnMouseEnter(thisPath, key, value) {
+  function setActiveItemDescriptionOnMouseEnter(thisPath: Array<string>, value: any) {
     if (!implementerToolsStore.getState().configPathBeingEdited) {
       const isLeaf = value && typeof value === 'object' && Object.hasOwn(value, '_value');
       implementerToolsStore.setState({
         activeItemDescription: {
           path: thisPath,
-          source: value._source,
-          description: value._description,
+          source: isLeaf ? value._source : undefined,
+          description: isLeaf ? value._description : undefined,
           value: isLeaf ? JSON.stringify(value._value) : undefined,
         },
       });
     }
   }
 
-  function removeActiveItemDescriptionOnMouseLeave(thisPath) {
+  function removeActiveItemDescriptionOnMouseLeave(thisPath: Array<string>) {
     const state = implementerToolsStore.getState();
     if (isEqual(state.activeItemDescription?.path, thisPath) && !isEqual(state.configPathBeingEdited, thisPath)) {
       implementerToolsStore.setState({ activeItemDescription: undefined });
@@ -35,14 +35,14 @@ export function ConfigSubtree({ config, path = [] }: ConfigSubtreeProps) {
     <>
       {Object.entries(config)
         .filter(([key]) => !key.startsWith('_'))
-        .map(([key, value], i) => {
+        .map(([key, value]) => {
           const thisPath = path.concat([key]);
           const isLeaf = value && typeof value === 'object' && Object.hasOwn(value, '_value');
           return (
             <Subtree
               label={key}
               leaf={isLeaf}
-              onMouseEnter={() => setActiveItemDescriptionOnMouseEnter(thisPath, key, value)}
+              onMouseEnter={() => setActiveItemDescriptionOnMouseEnter(thisPath, value)}
               onMouseLeave={() => removeActiveItemDescriptionOnMouseLeave(thisPath)}
               key={`subtree-${thisPath.join('.')}`}
             >