Address review feedback

- Replace Thread.sleep with sendAndWait in PRVisualization
- Fix top-level statements in multiple-sessions.md (wrap in class)
- Fix .getMessage() → .getData().content() in MultipleSessions.java
- Guard against null readLine() in AccessibilityReport.java
- Add null-safe getCause() + InterruptedException handling in ErrorHandling.java
- Fix paths: jbang commands now include recipe/ prefix
- Fix root README path: cd java/recipe (not java/cookbook/recipe)
- Fix recipe/README.md ralph-loop CLI example

cookbook/copilot-sdk/java/recipe/README.md

@@ -54,8 +54,10 @@ jbang PRVisualization.java github/copilot-sdk
 jbang ManagingLocalFiles.java /path/to/your/folder
 ```
 
-**Ralph Loop with a prompt file:**
+**Ralph Loop with a custom prompt file:**
 
+```bash
+jbang RalphLoop.java PROMPT_build.md 20
 ```
 
 ## Why JBang?