feat: add activity history, insights, and cat usage events

- Add activity history collection for cat usage events
- Add insight metrics (total cycles, average cycles, cycles today)
- Add cat usage events with weight for LR4
- Add intermediate state events (cycle started, cycle complete, etc.)
- Add pet visits_24h metric from weight history
- Add new LR4 metrics: lifetime_cycles, dfi_trigger_count, cat_detected
- Add configurable activity lookback window to prevent duplicate events
- Add API call delays to avoid rate limiting
- Update default poll interval to 5 minutes
- Update documentation with new metrics and events

.env.example

@@ -11,10 +11,16 @@ DATADOG_APP_KEY=your-datadog-app-key
 DATADOG_SITE=datadoghq.com
 
 # Collector settings
-DATACAT_POLL_INTERVAL=120
+DATACAT_POLL_INTERVAL=300
 DATACAT_INCLUDE_PETS=true
 DATACAT_EMIT_EVENTS=true
 DATACAT_METRIC_PREFIX=litterrobot
 
+# Activity and insights collection
+DATACAT_COLLECT_ACTIVITY=true
+DATACAT_COLLECT_INSIGHTS=true
+DATACAT_API_DELAY=1.0
+DATACAT_ACTIVITY_LOOKBACK=10
+
 # Optional: Path to config file (if using YAML config instead of env vars)
 # DATACAT_CONFIG_FILE=/path/to/config.yaml