[debugger] Add doc what to use instead of DebugProcessImpl.getManagerThread

GitOrigin-RevId: 527ae63f3048a14ae60b1fd7bf67b8fdd4ec3c3b

java/debugger/impl/src/com/intellij/debugger/engine/DebugProcessImpl.java

@@ -1176,6 +1176,11 @@ public abstract class DebugProcessImpl extends UserDataHolderBase implements Deb
     requestManager.setThreadFilter(null);
   }
 
+  /**
+   * Prefer using {@link SuspendContextImpl#getManagerThread()},
+   * {@link EvaluationContextImpl#getManagerThread()},
+   * or {@link DebuggerContextImpl#getManagerThread()} instead.
+   */
   @ApiStatus.Obsolete
   @Override
   public final @NotNull DebuggerManagerThreadImpl getManagerThread() {

java/debugger/impl/src/com/intellij/debugger/engine/evaluation/EvaluationContextImpl.java

@@ -78,7 +78,7 @@ public final class EvaluationContextImpl extends UserDataHolderBase implements E
     return getSuspendContext().getDebugProcess();
   }
 
-  public DebuggerManagerThreadImpl getManagerThread() {
+  public @NotNull DebuggerManagerThreadImpl getManagerThread() {
     return getSuspendContext().getManagerThread();
   }