Migrate generic-picker to new design (#27594)

* WIP new combo box

* Use new combo box for generic picker

* Fix esc close and clean up

* Fix empty search list item

* Fix picker usages

* Improve labels picker

* Patch WA to make esc on popover work correctly

* Apply suggestion from @piitaya

Co-authored-by: Paul Bottein <paul.bottein@gmail.com>

* Fix NO_MATCHING_ITEMS_FOUND_ID

* Fix possible undefined boolean props

---------

Co-authored-by: Paul Bottein <paul.bottein@gmail.com>

src/panels/lovelace/components/hui-entity-editor.ts

@@ -174,10 +174,10 @@ export class HuiEntityEditor extends LitElement {
             </div>
           </ha-sortable>`}
       <ha-entity-picker
-        class="add-entity"
         .hass=${this.hass}
         .entityFilter=${this.entityFilter}
         @value-changed=${this._addEntity}
+        add-button
       ></ha-entity-picker>
     `;
   }
@@ -226,13 +226,6 @@ export class HuiEntityEditor extends LitElement {
     ha-entity-picker {
       margin-top: 8px;
     }
-    .add-entity {
-      display: block;
-      margin-left: 31px;
-      margin-inline-start: 31px;
-      margin-inline-end: initial;
-      direction: var(--direction);
-    }
     .entity {
       display: flex;
       align-items: center;