State: sync post code blocks to repo exactly, split merged Red/Green/YellowState block, Java 25, H6 file labels, fix stale console output, README mapping

README.md

@@ -407,6 +407,25 @@ javac 03-behavioral/observer/*.java -d out/observer
 java -cp out/observer observer.Main
 ```
 
+### State (`03-behavioral/state/`)
+
+| Post Section | File(s) |
+|---|---|
+| With State: Traffic Light — the State interface | `TrafficLightState.java` |
+| With State: Traffic Light — the Context | `TrafficLight.java` |
+| With State: Traffic Light — RedState | `RedState.java` |
+| With State: Traffic Light — GreenState | `GreenState.java` |
+| With State: Traffic Light — YellowState | `YellowState.java` |
+| With State: Traffic Light — wiring it together | `Main.java` |
+
+Note: the "Without State: The if-else Machine" snippet is illustrative only — it is not part of this repository's runnable example.
+
+Run it:
+```bash
+javac 03-behavioral/state/*.java -d out/state
+java -cp out/state state.Main
+```
+
 ## Reference
 
 - *Design Patterns: Elements of Reusable Object-Oriented Software* — Gamma, Helm, Johnson, Vlissides