📚 Improve resources page organization and add tinyML course

🎓 Course Additions:
- Added CS 249r: Tiny Machine Learning (Harvard) to course list
- Covers TinyML systems, edge AI, and resource-constrained machine learning
- Complements existing MIT TinyML course with Harvard perspective

📖 Section Naming Fix:
- Changed 'Essential Books' → 'Recommended Books'
- Avoids prescriptive language and duplication issues
- More inclusive and less hierarchical phrasing

🔄 Organization Benefits:
- Eliminates potential confusion with ML Systems book already in courses
- Creates clearer separation between course materials and supplementary books
- Better reflects that these are helpful additions, not requirements

Result: More thoughtful resource organization with key Harvard tinyML
course addition and improved section naming.

book/resources.md

@@ -15,9 +15,12 @@ While TinyTorch teaches you to build ML systems from scratch, these resources pr
 - **[Machine Learning Systems](https://mlsysbook.ai)** by Prof. Vijay Janapa Reddi (Harvard)  
   *Comprehensive systems perspective on ML engineering and optimization*
 
-- **[CS 6.S965: TinyML and Efficient Deep Learning](https://hanlab.mit.edu/courses/2023-fall-65.2420/)** (MIT)  
+- **[CS 6.S965: TinyML and Efficient Deep Learning](https://hanlab.mit.edu/courses/2024-fall-65940)** (MIT)  
   *Edge computing, model compression, and efficient ML algorithms*
 
+- **[CS 249r: Tiny Machine Learning](https://sites.google.com/g.harvard.edu/tinyml/home)** (Harvard)  
+  *TinyML systems, edge AI, and resource-constrained machine learning*
+
 ### **Deep Learning Foundations**
 - **[CS 231n: Convolutional Neural Networks](http://cs231n.stanford.edu/)** (Stanford)  
   *Computer vision and CNN architectures - complements TinyTorch spatial modules*
@@ -27,7 +30,7 @@ While TinyTorch teaches you to build ML systems from scratch, these resources pr
 
 ---
 
-## 📖 **Essential Books**
+## 📖 **Recommended Books**
 
 ### **Systems & Engineering**
 - **"Designing Machine Learning Systems"** by Chip Huyen