Update README with Chapter 8 integration

Author: srikanthbaride

README.md

@@ -7,6 +7,7 @@
 [![ch5](https://github.com/srikanthbaride/Reinforcement-Learning-Explained-Code/actions/workflows/ch5.yml/badge.svg)](https://github.com/srikanthbaride/Reinforcement-Learning-Explained-Code/actions/workflows/ch5.yml)
 [![ch6](https://github.com/srikanthbaride/Reinforcement-Learning-Explained-Code/actions/workflows/ch6.yml/badge.svg)](https://github.com/srikanthbaride/Reinforcement-Learning-Explained-Code/actions/workflows/ch6.yml)
 [![ch7](https://github.com/srikanthbaride/Reinforcement-Learning-Explained-Code/actions/workflows/ch7.yml/badge.svg)](https://github.com/srikanthbaride/Reinforcement-Learning-Explained-Code/actions/workflows/ch7.yml)
+[![ch8](https://github.com/srikanthbaride/Reinforcement-Learning-Explained-Code/actions/workflows/ch8.yml/badge.svg)](https://github.com/srikanthbaride/Reinforcement-Learning-Explained-Code/actions/workflows/ch8.yml)
 
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@@ -22,6 +23,7 @@ It provides clean, minimal, and well-tested implementations of key reinforcement
 - [Chapter 5: Monte Carlo Methods](./ch5_monte_carlo)
 - [Chapter 6: Temporal-Difference Learning](./ch6_td_learning)
 - [Chapter 7: TD Control — SARSA and Q-Learning](./ch7_td_control)
+- [Chapter 8: Eligibility Traces and TD(λ)](./ch8_td_lambda)
 
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@@ -36,7 +38,7 @@ It provides clean, minimal, and well-tested implementations of key reinforcement
 | 5       | Monte Carlo Methods            | ✅ Complete    | Prediction, Control, On/Off-Policy                  |
 | 6       | Temporal-Difference Learning   | ✅ Complete    | TD(0), n-step TD, prediction examples               |
 | 7       | TD Control                     | ✅ Complete    | SARSA, Q-learning, Cliff-Walking, exploration       |
-| 8+      | Advanced TD / Function Approx. | ⏳ In Progress | Eligibility Traces, Deadly Triad, etc.              |
+| 8       | Eligibility Traces and TD(λ)   | ✅ Complete    | TD(λ), SARSA(λ), True Online TD(λ), gridworld demos |
 
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@@ -50,6 +52,7 @@ rl-fundamentals-code/
 ├─ ch5_monte_carlo/                # Chapter 5
 ├─ ch6_td_learning/                # Chapter 6
 ├─ ch7_td_control/                 # Chapter 7
+├─ ch8_td_lambda/                  # Chapter 8
 ├─ utils/
 └─ .github/workflows/
 ```
@@ -64,10 +67,10 @@ To run all tests:
 python -m pytest -q
 ```
 
-Run only Chapter 7 tests:
+Run only Chapter 8 tests:
 
 ```bash
-python -m pytest -q tests/test_ch7_td_control.py
+python -m pytest -q ch8_td_lambda/tests
 ```
 
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