Fix missing helper for entity picker (#25622)

src/components/entity/ha-entity-picker.ts

@@ -390,6 +390,7 @@ export class HaEntityPicker extends LitElement {
         .autofocus=${this.autofocus}
         .allowCustomValue=${this.allowCustomEntity}
         .label=${this.label}
+        .helper=${this.helper}
         .searchLabel=${this.searchLabel}
         .notFoundLabel=${notFoundLabel}
         .placeholder=${placeholder}

src/components/ha-generic-picker.ts

@@ -104,8 +104,8 @@ export class HaGenericPicker extends LitElement {
                 .getAdditionalItems=${this.getAdditionalItems}
               ></ha-picker-combo-box>
             `}
-        ${this._renderHelper()}
       </div>
+      ${this._renderHelper()}
     `;
   }
 
@@ -164,6 +164,10 @@ export class HaGenericPicker extends LitElement {
           display: block;
           margin: 0 0 8px;
         }
+        ha-input-helper-text {
+          display: block;
+          margin: 8px 0 0;
+        }
       `,
     ];
   }