mqtt_overlays.json: добавлены HA Assist question / response overlays

Подписка на assist/conversation/text + /response (plain-text retained,
schema см. home-assistant/.../assist_mqtt.md).

Позиция: левый-нижний угол стопкой —
  🤖 ответ внизу (margin_y=32)
  🗣 вопрос выше (margin_y=78)

Полупрозрачная подложка (bg_alpha=180), placeholder с эмодзи пока
turn'а не было.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

docker/mqtt_overlays.json

@@ -15,6 +15,38 @@
       "color": [255, 255, 255],
       "alpha": 230,
       "font_path": "/fonts/DejaVuSans-Bold.ttf"
+    },
+    {
+      "id": "assist_question",
+      "_doc": "Последний вопрос пользователя к HA Assist. Plain-text retained.",
+      "topic": "assist/conversation/text",
+      "json_field": "",
+      "format": "🗣 %s",
+      "anchor": "left-bottom",
+      "margin_x": 32,
+      "margin_y": 78,
+      "pixel_size": 22,
+      "color": [200, 220, 255],
+      "alpha": 230,
+      "bg_alpha": 180,
+      "bg_pad": 10,
+      "placeholder": "🗣 ..."
+    },
+    {
+      "id": "assist_response",
+      "_doc": "Ответ HA Assist последнего turn'а. Plain-text retained.",
+      "topic": "assist/conversation/response",
+      "json_field": "",
+      "format": "🤖 %s",
+      "anchor": "left-bottom",
+      "margin_x": 32,
+      "margin_y": 32,
+      "pixel_size": 22,
+      "color": [255, 255, 255],
+      "alpha": 230,
+      "bg_alpha": 180,
+      "bg_pad": 10,
+      "placeholder": "🤖 ..."
     }
   ]
 }