Add profile conditions, scene presets, MQTT integration, and Scenes tab

Feature 1 — Profile Conditions: time-of-day, system idle (Win32
GetLastInputInfo), and display state (GUID_CONSOLE_DISPLAY_STATE)
condition types for automatic profile activation.

Feature 2 — Scene Presets: snapshot/restore system that captures target
running states, device brightness, and profile enables. Server-side
capture with 5-step activation order. Dedicated Scenes tab with
CardSection-based card grid, command palette integration, and dashboard
quick-activate section.

Feature 3 — MQTT Integration: MQTTService singleton with aiomqtt,
MQTTLEDClient device provider for pixel output, MQTT profile condition
type with topic/payload matching, and frontend support for MQTT device
type and condition editor.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/wled_controller/static/locales/zh.json

@@ -128,6 +128,9 @@
   "device.led_type.hint": "RGB（3通道）或 RGBW（4通道，带独立白色）",
   "device.send_latency": "发送延迟（毫秒）：",
   "device.send_latency.hint": "每帧模拟网络/串口延迟（毫秒）",
+  "device.mqtt_topic": "MQTT 主题：",
+  "device.mqtt_topic.hint": "用于发布像素数据的 MQTT 主题路径（例如 mqtt://ledgrab/device/name）",
+  "device.mqtt_topic.placeholder": "mqtt://ledgrab/device/客厅",
   "device.url.hint": "设备的 IP 地址或主机名（例如 http://192.168.1.100）",
   "device.name": "设备名称：",
   "device.name.placeholder": "客厅电视",
@@ -529,6 +532,7 @@
   "dashboard.stop_all": "全部停止",
   "dashboard.failed": "加载仪表盘失败",
   "dashboard.section.profiles": "配置文件",
+  "dashboard.section.scenes": "场景预设",
   "dashboard.targets": "目标",
   "dashboard.section.performance": "系统性能",
   "dashboard.perf.cpu": "CPU",
@@ -568,6 +572,27 @@
   "profiles.condition.application.match_type.topmost": "最前（前台）",
   "profiles.condition.application.match_type.topmost_fullscreen": "最前 + 全屏",
   "profiles.condition.application.match_type.fullscreen": "全屏",
+  "profiles.condition.time_of_day": "时段",
+  "profiles.condition.time_of_day.start_time": "开始时间：",
+  "profiles.condition.time_of_day.end_time": "结束时间：",
+  "profiles.condition.time_of_day.overnight_hint": "跨夜时段（如 22:00–06:00），请将开始时间设为晚于结束时间。",
+  "profiles.condition.system_idle": "系统空闲",
+  "profiles.condition.system_idle.idle_minutes": "空闲超时（分钟）：",
+  "profiles.condition.system_idle.mode": "触发模式：",
+  "profiles.condition.system_idle.when_idle": "空闲时",
+  "profiles.condition.system_idle.when_active": "活跃时",
+  "profiles.condition.display_state": "显示器状态",
+  "profiles.condition.display_state.state": "显示器状态：",
+  "profiles.condition.display_state.on": "开启",
+  "profiles.condition.display_state.off": "关闭（休眠）",
+  "profiles.condition.mqtt": "MQTT",
+  "profiles.condition.mqtt.topic": "主题：",
+  "profiles.condition.mqtt.payload": "消息内容：",
+  "profiles.condition.mqtt.match_mode": "匹配模式：",
+  "profiles.condition.mqtt.match_mode.exact": "精确匹配",
+  "profiles.condition.mqtt.match_mode.contains": "包含",
+  "profiles.condition.mqtt.match_mode.regex": "正则表达式",
+  "profiles.condition.mqtt.hint": "当 MQTT 主题收到匹配的消息时激活",
   "profiles.targets": "目标：",
   "profiles.targets.hint": "配置文件激活时要启动的目标",
   "profiles.targets.empty": "没有可用的目标",
@@ -586,6 +611,36 @@
   "profiles.error.name_required": "名称为必填项",
   "profiles.toggle_all.start": "启动所有目标",
   "profiles.toggle_all.stop": "停止所有目标",
+  "scenes.title": "场景",
+  "scenes.add": "捕获场景",
+  "scenes.edit": "编辑场景",
+  "scenes.name": "名称：",
+  "scenes.name.hint": "此场景预设的描述性名称",
+  "scenes.description": "描述：",
+  "scenes.description.hint": "此场景功能的可选描述",
+  "scenes.color": "卡片颜色：",
+  "scenes.color.hint": "仪表盘上场景卡片的强调色",
+  "scenes.capture": "捕获",
+  "scenes.activate": "激活场景",
+  "scenes.recapture": "重新捕获当前状态",
+  "scenes.delete": "删除场景",
+  "scenes.targets_count": "目标",
+  "scenes.devices_count": "设备",
+  "scenes.profiles_count": "配置",
+  "scenes.captured": "场景已捕获",
+  "scenes.updated": "场景已更新",
+  "scenes.activated": "场景已激活",
+  "scenes.activated_partial": "场景部分激活",
+  "scenes.errors": "错误",
+  "scenes.recaptured": "场景已重新捕获",
+  "scenes.deleted": "场景已删除",
+  "scenes.recapture_confirm": "将当前状态重新捕获到\"{name}\"中？",
+  "scenes.delete_confirm": "删除场景\"{name}\"？",
+  "scenes.error.name_required": "名称为必填项",
+  "scenes.error.save_failed": "保存场景失败",
+  "scenes.error.activate_failed": "激活场景失败",
+  "scenes.error.recapture_failed": "重新捕获场景失败",
+  "scenes.error.delete_failed": "删除场景失败",
   "autostart.title": "自动启动目标",
   "autostart.toggle.enabled": "自动启动已启用",
   "autostart.toggle.disabled": "自动启动已禁用",
@@ -961,6 +1016,7 @@
   "search.group.pattern_templates": "图案模板",
   "search.group.audio": "音频源",
   "search.group.value": "值源",
+  "search.group.scenes": "场景预设",
   "settings.backup.label": "备份配置",
   "settings.backup.hint": "将所有配置（设备、目标、流、模板、配置文件）下载为单个 JSON 文件。",
   "settings.backup.button": "下载备份",