Use forRemoval/since on deprecated NIMBUS_SUPERVISOR_TIMEOUT_SECS

Match Storm's existing deprecation convention (e.g. Config.java) by marking
the unused constant @deprecated(forRemoval = true, since = "3.0.1") and stating
in the javadoc that it is scheduled for removal. 3.0.1 is the current
development version (root pom is 3.0.1-SNAPSHOT).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: reiabreu

storm-server/src/main/java/org/apache/storm/DaemonConfig.java

@@ -281,9 +281,10 @@ public class DaemonConfig implements Validated {
      * @deprecated Unused. Supervisor liveness is tracked via an ephemeral ZooKeeper node (see
      *     {@code StormClusterState#supervisorHeartbeat}); when a supervisor dies its ZooKeeper session
      *     expires and the node disappears, so Nimbus detects the loss directly rather than by timing out
-     *     heartbeats. No code reads this value. Retained only for backward compatibility.
+     *     heartbeats. No code reads this value. It is scheduled for removal; retained for now only for
+     *     backward compatibility.
      */
-    @Deprecated
+    @Deprecated(forRemoval = true, since = "3.0.1")
     @IsInteger
     @IsPositiveNumber
     public static final String NIMBUS_SUPERVISOR_TIMEOUT_SECS = "nimbus.supervisor.timeout.secs";