Add homeassistant-event-gateway template

[canuto]

Summary

• Adds a new template for receiving Home Assistant events via webhook
• Implements rules-based noise filtering to reduce notification fatigue
• Forwards notable events to Slack with optional AI explanations
• Home Assistant stays in control of devices - this is a read-only event gateway

Features

Feature	Description
Webhook endpoint	POST /ha/event with secure token authentication via webhook-verify
Event storage	Normalized schema in ha_events collection
Deduplication	Ignores identical events within configurable window
Burst detection	Flags rapid repeated triggers from same entity
Time-of-day	Night-time motion/door events flagged as notable
Entity filtering	Allowlist/denylist with wildcard support
Slack notifications	Block Kit formatting with entity emojis
AI explanations	Optional OpenAI/Anthropic integration
Daily digest	GET /ha/digest with statistics

Dependencies

• Uses webhook-verify@0.2 which has native Home Assistant support for secure constant-time token comparison

Files

homeassistant-event-gateway/
├── .env.example        # Environment variable documentation
├── .gitignore
├── package.json
├── README.md           # Comprehensive docs with HA YAML examples
└── src/
    ├── index.js        # Routes and handlers
    ├── rules.js        # Noise filtering logic
    ├── slack.js        # Slack message formatting
    └── ai.js           # Optional LLM explanations

Test plan

• Deploy template to a test Codehooks project
• Verify webhook accepts events with correct secret
• Verify webhook rejects events without secret
• Test deduplication by sending same event twice
• Test Slack notification formatting
• Test digest endpoint returns correct statistics

🤖 Generated with Claude Code