Enhance /notify with custom emote, color, animation, sound

- /notify now accepts optional: emote, color, animation, sound
- Backend passes custom properties to status response
- Frontend handles custom sounds (chime, alert, success, etc.)
- Added new sound effects: chime, alert, success
- Updated documentation with full notify options
- Added HA automation examples for doorbell and timer

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CLAUDE.md

@@ -73,12 +73,34 @@ All detectors support: `AGGREGATOR_URL`, `CHECK_INTERVAL`, `THRESHOLD_WARNING`,
 |----------|--------|-------------|
 | `/event` | POST | Register event: `{"id": "name", "priority": 1-4, "message": "optional", "ttl": seconds}` |
 | `/clear` | POST | Clear event: `{"id": "name"}` |
-| `/notify` | POST | Simple notification: `{"message": "text", "duration": 5}` |
+| `/notify` | POST | Notification with optional customization (see below) |
 | `/sleep` | POST | Enter sleep mode |
 | `/wake` | POST | Exit sleep mode |
 | `/status` | GET | Current state JSON |
 | `/events` | GET | List active events |
 
+### `/notify` Endpoint
+
+```json
+{
+  "message": "Someone at the door",
+  "duration": 10,
+  "emote": "( °o°)",
+  "color": "#FF9900",
+  "animation": "popping",
+  "sound": "chime"
+}
+```
+
+| Field | Required | Description |
+|-------|----------|-------------|
+| `message` | No | Text to display below emote |
+| `duration` | No | Seconds before auto-expire (default: 5) |
+| `emote` | No | Custom emote to display |
+| `color` | No | Custom color (hex, e.g., `#FF9900`) |
+| `animation` | No | One of: `breathing`, `shaking`, `popping`, `celebrating`, `floating`, `bouncing`, `swaying` |
+| `sound` | No | One of: `chime`, `alert`, `warning`, `critical`, `success`, `notify`, `none` |
+
 ## Priority System
 
 Lower number = higher priority. Events with a `ttl` auto-expire (heartbeat pattern).