Use regular item for bottom padding in combobox

When tsc receives file arguments, it ignores tsconfig.json and emits
.js files into src/, polluting the codebase. This documents the issue
and provides cleanup instructions.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.github/copilot-instructions.md

@@ -22,11 +22,13 @@ You are an assistant helping with development of the Home Assistant frontend. Th
 ```bash
 yarn lint          # ESLint + Prettier + TypeScript + Lit
 yarn format        # Auto-fix ESLint + Prettier
-yarn lint:types    # TypeScript compiler
+yarn lint:types    # TypeScript compiler (run WITHOUT file arguments)
 yarn test          # Vitest
 script/develop     # Development server
 ```
 
+> **WARNING:** Never run `tsc` or `yarn lint:types` with file arguments (e.g., `yarn lint:types src/file.ts`). When `tsc` receives file arguments, it ignores `tsconfig.json` and emits `.js` files into `src/`, polluting the codebase. Always run `yarn lint:types` without arguments. For individual file type checking, rely on IDE diagnostics. If `.js` files are accidentally generated, clean up with `git clean -fd src/`.
+
 ### Component Prefixes
 
 - `ha-` - Home Assistant components

src/components/ha-picker-combo-box.ts

@@ -55,6 +55,7 @@ export interface PickerComboBoxItem {
 }
 
 export const NO_ITEMS_AVAILABLE_ID = "___no_items_available___";
+const PADDING_ID = "___padding___";
 
 const DEFAULT_ROW_RENDERER: RenderItemFunction<PickerComboBoxItem> = (
   item
@@ -108,7 +109,7 @@ export class HaPickerComboBox extends ScrollableFadeMixin(LitElement) {
   public getItems!: (
     searchString?: string,
     section?: string
-  ) => (PickerComboBoxItem | string)[];
+  ) => PickerComboBoxItem[];
 
   @property({ attribute: false, type: Array })
   public getAdditionalItems?: (searchString?: string) => PickerComboBoxItem[];
@@ -150,7 +151,7 @@ export class HaPickerComboBox extends ScrollableFadeMixin(LitElement) {
 
   @query("ha-textfield") private _searchFieldElement?: HaTextField;
 
-  @state() private _items: (PickerComboBoxItem | string)[] = [];
+  @state() private _items: PickerComboBoxItem[] = [];
 
   protected get scrollableElement(): HTMLElement | null {
     return this._virtualizerElement as HTMLElement | null;
@@ -160,7 +161,7 @@ export class HaPickerComboBox extends ScrollableFadeMixin(LitElement) {
 
   @state() private _valuePinned = true;
 
-  private _allItems: (PickerComboBoxItem | string)[] = [];
+  private _allItems: PickerComboBoxItem[] = [];
 
   private _selectedItemIndex = -1;
 
@@ -278,8 +279,8 @@ export class HaPickerComboBox extends ScrollableFadeMixin(LitElement) {
       this._sectionTitle = this.sectionTitleFunction({
         firstIndex: ev.first,
         lastIndex: ev.last,
-        firstItem: firstItem as PickerComboBoxItem | string,
-        secondItem: secondItem as PickerComboBoxItem | string,
+        firstItem: firstItem as PickerComboBoxItem,
+        secondItem: secondItem as PickerComboBoxItem,
         itemsCount: this._virtualizerElement.items.length,
       });
     }
@@ -324,27 +325,27 @@ export class HaPickerComboBox extends ScrollableFadeMixin(LitElement) {
     }
 
     if (!items.length) {
-      items.push(NO_ITEMS_AVAILABLE_ID);
+      items.push({ id: NO_ITEMS_AVAILABLE_ID, primary: "" });
     }
 
     const additionalItems = this._getAdditionalItems();
     items.push(...additionalItems);
 
     if (this.mode === "dialog") {
-      items.push("padding"); // padding for safe area inset
+      items.push({ id: PADDING_ID, primary: "" }); // padding for safe area inset
     }
 
     return items;
   };
 
-  private _renderItem = (item: PickerComboBoxItem | string, index: number) => {
+  private _renderItem = (item: PickerComboBoxItem, index: number) => {
     if (!item) {
       return nothing;
     }
-    if (item === "padding") {
+    if (item.id === PADDING_ID) {
       return html`<div class="bottom-padding"></div>`;
     }
-    if (item === NO_ITEMS_AVAILABLE_ID) {
+    if (item.id === NO_ITEMS_AVAILABLE_ID) {
       return html`
         <div class="combo-box-row">
           <ha-combo-box-item type="text" compact>
@@ -419,21 +420,18 @@ export class HaPickerComboBox extends ScrollableFadeMixin(LitElement) {
         return;
       }
 
-      const index = this._fuseIndex(
-        this._allItems as PickerComboBoxItem[],
-        this.searchKeys
-      );
+      const index = this._fuseIndex(this._allItems, this.searchKeys);
 
       let filteredItems = multiTermSortedSearch<PickerComboBoxItem>(
-        this._allItems as PickerComboBoxItem[],
+        this._allItems,
         searchString,
         this.searchKeys || DEFAULT_SEARCH_KEYS,
         (item) => item.id,
         index
-      ) as (PickerComboBoxItem | string)[];
+      );
 
       if (!filteredItems.length) {
-        filteredItems.push(NO_ITEMS_AVAILABLE_ID);
+        filteredItems.push({ id: NO_ITEMS_AVAILABLE_ID, primary: "" });
       }
 
       const additionalItems = this._getAdditionalItems(searchString);
@@ -442,8 +440,8 @@ export class HaPickerComboBox extends ScrollableFadeMixin(LitElement) {
       if (this.searchFn) {
         filteredItems = this.searchFn(
           searchString,
-          filteredItems as PickerComboBoxItem[],
-          this._allItems as PickerComboBoxItem[]
+          filteredItems,
+          this._allItems
         );
       }
 
@@ -459,7 +457,7 @@ export class HaPickerComboBox extends ScrollableFadeMixin(LitElement) {
         });
       }
 
-      this._items = filteredItems as PickerComboBoxItem[];
+      this._items = filteredItems;
     }
 
     this._selectedItemIndex = -1;