[CURATOR-727] Add the ability to run watches asynchronously via an executor

This would modify NamespaceWatcher such that the process() method would run the provided watcher instance in an ExecutorService, if the CuratorFramework was setup to use an asyncWatchService.

This way long-running watch code does not block the original command (if run in the foreground), or other watchers for the same event.

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Originally reported by houston, imported from: Add the ability to run watches asynchronously via an executor

• status: Open
  
• priority: Major
  
• resolution: Unresolved
  
• imported: 2025-01-21