feat: server telemetry, update entity, sync-clock controls

- Server device exposing CPU/RAM/GPU/temperature/battery sensors via
  /api/v1/system/performance, plus last-restart timestamp (cached with
  jitter threshold so the recorder doesn't see poll wobble) and version.
- Update entity backed by /api/v1/system/update — installs via
  /apply, hides the install button when the server reports
  can_auto_update=false.
- Sync-clock entities: reset button, speed number, running switch, and
  the event listener now refreshes on entity_changed events too.
- Bump manifest to 0.4.0.

custom_components/ledgrab/translations/ru.json

@@ -29,6 +29,9 @@
     "button": {
       "activate_scene": {
         "name": "{scene_name}"
+      },
+      "sync_clock_reset": {
+        "name": "Сброс"
       }
     },
     "light": {
@@ -39,6 +42,9 @@
     "switch": {
       "processing": {
         "name": "Обработка"
+      },
+      "sync_clock_running": {
+        "name": "Активно"
       }
     },
     "sensor": {
@@ -56,6 +62,39 @@
       },
       "mapped_lights": {
         "name": "Привязанные светильники"
+      },
+      "sync_clock_elapsed": {
+        "name": "Прошло времени"
+      },
+      "server_cpu_percent": {
+        "name": "Загрузка CPU"
+      },
+      "server_ram_percent": {
+        "name": "Загрузка ОЗУ"
+      },
+      "server_app_cpu_percent": {
+        "name": "CPU приложения"
+      },
+      "server_app_ram": {
+        "name": "Память приложения"
+      },
+      "server_gpu_utilization": {
+        "name": "Загрузка GPU"
+      },
+      "server_gpu_temp": {
+        "name": "Температура GPU"
+      },
+      "server_cpu_temp": {
+        "name": "Температура CPU"
+      },
+      "server_battery": {
+        "name": "Батарея"
+      },
+      "server_last_restart": {
+        "name": "Последний запуск"
+      },
+      "server_version": {
+        "name": "Версия сервера"
       }
     },
     "number": {
@@ -76,6 +115,9 @@
       },
       "api_input_timeout": {
         "name": "Таймаут подмены"
+      },
+      "sync_clock_speed": {
+        "name": "Скорость"
       }
     },
     "select": {
@@ -93,6 +135,11 @@
           "nearest": "Ближайший"
         }
       }
+    },
+    "update": {
+      "server_update": {
+        "name": "Обновление сервера"
+      }
     }
   }
 }