delete units 2,3,4

Author: burtenshaw

units/en/_toctree.yml

@@ -18,55 +18,13 @@
   sections:
   - local: unit2/introduction
     title: Understanding MCP Architecture and Core Concepts
-  - local: unit2/architectural-components
-    title: Architectural Components
-  - local: unit2/communication-protocol
-    title: The Communication Protocol
-  - local: unit2/capabilities
-    title: Understanding MCP Capabilities
-  - local: unit2/quiz2
-    title: Unit 2 Quiz
 
 - title: "3. Building with MCP: Practical Development"
   sections:
   - local: unit3/introduction
     title: Introduction
-  - local: unit3/environment-setup
-    title: Setting Up Your Development Environment & SDKs
-  - local: unit3/building-server
-    title: Building Your First MCP Server
-  - local: unit3/server-capabilities
-    title: Implementing Server Capabilities
-  - local: unit3/developing-clients
-    title: Developing MCP Clients
-  - local: unit3/configuration
-    title: Configuration, Authentication, and Debugging
-  - local: unit3/mcp-ecosystem
-    title: Navigating the MCP Ecosystem
-  - local: unit3/gradio-mcp
-    title: Gradio MCP Integration
-  - local: unit3/hub-mcp-servers
-    title: MCP Servers on Hugging Face Hub
-  - local: unit3/practical-exercise
-    title: Practical Exercise on MCP Interaction Walkthrough
-  - local: unit3/quiz
-    title: Unit 3 Quiz
 
 - title: "4. Advanced Topics, Security, and the Future of MCP"
   sections:
   - local: unit4/introduction
     title: Introduction
-  - local: unit4/advanced-features
-    title: Exploring Advanced MCP Features
-  - local: unit4/security
-    title: Security Deep Dive - Threats and Mitigation Strategies
-  - local: unit4/limitations
-    title: Limitations, Challenges, and Comparisons
-  - local: unit4/huggingface-ecosystem
-    title: Hugging Face's Ecosystem and Future Contributions
-  - local: unit4/future
-    title: The Future of MCP - Roadmap and Standardization
-  - local: unit4/final-project
-    title: Final Project - Building a Complete MCP Application
-  - local: unit4/certification
-    title: Certification and Next Steps