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/en.json

@@ -128,6 +128,9 @@
   "device.led_type.hint": "RGB (3 channels) or RGBW (4 channels with dedicated white)",
   "device.send_latency": "Send Latency (ms):",
   "device.send_latency.hint": "Simulated network/serial delay per frame in milliseconds",
+  "device.mqtt_topic": "MQTT Topic:",
+  "device.mqtt_topic.hint": "MQTT topic path for publishing pixel data (e.g. mqtt://ledgrab/device/name)",
+  "device.mqtt_topic.placeholder": "mqtt://ledgrab/device/living-room",
   "device.url.hint": "IP address or hostname of the device (e.g. http://192.168.1.100)",
   "device.name": "Device Name:",
   "device.name.placeholder": "Living Room TV",
@@ -529,6 +532,7 @@
   "dashboard.stop_all": "Stop All",
   "dashboard.failed": "Failed to load dashboard",
   "dashboard.section.profiles": "Profiles",
+  "dashboard.section.scenes": "Scene Presets",
   "dashboard.targets": "Targets",
   "dashboard.section.performance": "System Performance",
   "dashboard.perf.cpu": "CPU",
@@ -568,6 +572,27 @@
   "profiles.condition.application.match_type.topmost": "Topmost (foreground)",
   "profiles.condition.application.match_type.topmost_fullscreen": "Topmost + Fullscreen",
   "profiles.condition.application.match_type.fullscreen": "Fullscreen",
+  "profiles.condition.time_of_day": "Time of Day",
+  "profiles.condition.time_of_day.start_time": "Start Time:",
+  "profiles.condition.time_of_day.end_time": "End Time:",
+  "profiles.condition.time_of_day.overnight_hint": "For overnight ranges (e.g. 22:00–06:00), set start time after end time.",
+  "profiles.condition.system_idle": "System Idle",
+  "profiles.condition.system_idle.idle_minutes": "Idle Timeout (minutes):",
+  "profiles.condition.system_idle.mode": "Trigger Mode:",
+  "profiles.condition.system_idle.when_idle": "When idle",
+  "profiles.condition.system_idle.when_active": "When active",
+  "profiles.condition.display_state": "Display State",
+  "profiles.condition.display_state.state": "Monitor State:",
+  "profiles.condition.display_state.on": "On",
+  "profiles.condition.display_state.off": "Off (sleeping)",
+  "profiles.condition.mqtt": "MQTT",
+  "profiles.condition.mqtt.topic": "Topic:",
+  "profiles.condition.mqtt.payload": "Payload:",
+  "profiles.condition.mqtt.match_mode": "Match Mode:",
+  "profiles.condition.mqtt.match_mode.exact": "Exact",
+  "profiles.condition.mqtt.match_mode.contains": "Contains",
+  "profiles.condition.mqtt.match_mode.regex": "Regex",
+  "profiles.condition.mqtt.hint": "Activate when an MQTT topic receives a matching payload",
   "profiles.targets": "Targets:",
   "profiles.targets.hint": "Targets to start when this profile activates",
   "profiles.targets.empty": "No targets available",
@@ -586,6 +611,36 @@
   "profiles.error.name_required": "Name is required",
   "profiles.toggle_all.start": "Start all targets",
   "profiles.toggle_all.stop": "Stop all targets",
+  "scenes.title": "Scenes",
+  "scenes.add": "Capture Scene",
+  "scenes.edit": "Edit Scene",
+  "scenes.name": "Name:",
+  "scenes.name.hint": "A descriptive name for this scene preset",
+  "scenes.description": "Description:",
+  "scenes.description.hint": "Optional description of what this scene does",
+  "scenes.color": "Card Color:",
+  "scenes.color.hint": "Accent color for the scene card on the dashboard",
+  "scenes.capture": "Capture",
+  "scenes.activate": "Activate scene",
+  "scenes.recapture": "Recapture current state",
+  "scenes.delete": "Delete scene",
+  "scenes.targets_count": "targets",
+  "scenes.devices_count": "devices",
+  "scenes.profiles_count": "profiles",
+  "scenes.captured": "Scene captured",
+  "scenes.updated": "Scene updated",
+  "scenes.activated": "Scene activated",
+  "scenes.activated_partial": "Scene partially activated",
+  "scenes.errors": "errors",
+  "scenes.recaptured": "Scene recaptured",
+  "scenes.deleted": "Scene deleted",
+  "scenes.recapture_confirm": "Recapture current state into \"{name}\"?",
+  "scenes.delete_confirm": "Delete scene \"{name}\"?",
+  "scenes.error.name_required": "Name is required",
+  "scenes.error.save_failed": "Failed to save scene",
+  "scenes.error.activate_failed": "Failed to activate scene",
+  "scenes.error.recapture_failed": "Failed to recapture scene",
+  "scenes.error.delete_failed": "Failed to delete scene",
   "autostart.title": "Auto-start Targets",
   "autostart.toggle.enabled": "Auto-start enabled",
   "autostart.toggle.disabled": "Auto-start disabled",
@@ -961,6 +1016,7 @@
   "search.group.pattern_templates": "Pattern Templates",
   "search.group.audio": "Audio Sources",
   "search.group.value": "Value Sources",
+  "search.group.scenes": "Scene Presets",
   "settings.backup.label": "Backup Configuration",
   "settings.backup.hint": "Download all configuration (devices, targets, streams, templates, profiles) as a single JSON file.",
   "settings.backup.button": "Download Backup",