Fix chapter numbering in navigation

Corrected navigation to show proper chapter numbers 1-16, with Introduction before Chapter 1, and Conclusion/Appendix at the end. Now reflects the actual book structure.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: DavidLiedle

_config.yml

@@ -58,41 +58,41 @@ navigation:
     url: "/01-table-of-contents"
   - title: "Introduction"
     url: "/02-introduction"
-  - title: "Chapter 3: Why React Exists"
+  - title: "1. Why React Exists"
     url: "/03-chapter-why-react-exists"
-  - title: "Chapter 4: JavaScript Fatigue"
+  - title: "2. JavaScript Fatigue"
     url: "/04-chapter-javascript-fatigue"
-  - title: "Chapter 5: Virtual DOM Lie"
+  - title: "3. The Virtual DOM"
     url: "/05-chapter-virtual-dom-lie"
-  - title: "Chapter 6: JSX Abomination"
+  - title: "4. JSX"
     url: "/06-chapter-jsx-abomination"
-  - title: "Chapter 7: Components Everywhere"
+  - title: "5. Components"
     url: "/07-chapter-components-everywhere"
-  - title: "Chapter 8: State Management Hell"
+  - title: "6. State Management"
     url: "/08-chapter-state-management-hell"
-  - title: "Chapter 9: Hooks Magic"
+  - title: "7. Hooks"
     url: "/09-chapter-hooks-magic"
-  - title: "Chapter 10: Effects Footguns"
+  - title: "8. useEffect"
     url: "/10-chapter-effects-footguns"
-  - title: "Chapter 11: Props Drilling"
+  - title: "9. Props Drilling"
     url: "/11-chapter-props-drilling"
-  - title: "Chapter 12: Patterns & Anti-patterns"
+  - title: "10. Patterns & Anti-patterns"
     url: "/12-chapter-patterns-antipatterns"
-  - title: "Chapter 13: Performance Myths"
+  - title: "11. Performance"
     url: "/13-chapter-performance-myths"
-  - title: "Chapter 14: Testing Nightmare"
+  - title: "12. Testing"
     url: "/14-chapter-testing-nightmare"
-  - title: "Chapter 15: Tooling Ecosystem"
+  - title: "13. The Ecosystem"
     url: "/15-chapter-tooling-ecosystem"
-  - title: "Chapter 16: Real World App"
+  - title: "14. Building a Real App"
     url: "/16-chapter-real-world-app"
-  - title: "Chapter 17: Alternatives"
+  - title: "15. Alternatives"
     url: "/17-chapter-alternatives-grass"
-  - title: "Chapter 18: Acceptance"
+  - title: "16. Acceptance"
     url: "/18-chapter-acceptance"
-  - title: "Chapter 19: Conclusion"
+  - title: "Conclusion"
     url: "/19-conclusion"
-  - title: "Appendix: Resources"
+  - title: "Appendix"
     url: "/20-appendix-resources"
 
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