Add AI Assistant link and badge to README

[namandhakad712]

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🚀 Pull Request: Integrate Zread.ai for Semantic Repo Indexing

Description
This PR integrates Zread.ai into the OpenFlowKit README. Zread is an AI-powered indexing engine that transforms our repository into a searchable knowledge base, allowing users to interact with the codebase using natural language.

🛠️ Changes

• AI-Navigation: Added a bold "Ask AI Assistant" link to the header nav.
• Semantic Badge: Placed a large, centered "Ask Zread" badge to encourage interactive exploration.
• Repo Indexing: Linked the project to its semantic index at zread.ai/Vrun-design/openflowkit.

🧠 What is Zread.ai & Why add it?

Unlike standard documentation, Zread indexes the entire repository at the code level.

• Semantic Code Search: Builders can ask "How is the cinematic export handled?" or "Where are the React 19 types defined?" and get instant, context-aware answers.
• Deep Context: It understands the relationships between our components, hooks, and local-first storage logic.
• Zero-Friction Support: Reduces the number of repetitive issues by letting the AI explain the "how" and "why" behind the source code directly to the user.

📸 Preview

The project header now features a professional AI entry point, making it easier for new contributors to navigate our Vite 6 + React 19 architecture without getting lost in the file tree.

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