Add model-redis package references to documentation

- Added ORM reference in architecture.md (Redis section)
- Added Data Models section in contributing.md with example
- Updated README.md to mention model-redis in Architecture
- Linked to https://www.npmjs.com/package/model-redis for more info

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

README.md

@@ -147,7 +147,7 @@ The system consists of three main components:
    - Host lookup tree with wildcard matching
    - User authentication and authorization
 
-3. **Redis** - Data store
+3. **Redis** - Data store (using [model-redis](https://www.npmjs.com/package/model-redis) ORM)
    - Host configurations
    - User accounts and tokens
    - SSL certificate storage