Extend Category Schema with slug Field

[ashen-dusk]

🎯 Goal

Add a slug field to the Category schema for frontend-friendly URLs, and update existing backend queries and mutations to support it.

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✅ Requirements

• • Add a new slug field (type: String, unique, non-null) to the Category model.
• • Generate slugs automatically based on the category name (e.g. AI Tools → ai-tools).
• • Update the relevant queries and mutations if needed:.
• • Verify slug generation and retrieval logic.