[JENKINS-5399] Need 'run a command on master to shutdown this slave'

We can start slaves via 'run a command on master' but shutting them down would be most convenient if a separate comand was run.

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Originally reported by lifeless, imported from: Need 'run a command on master to shutdown this slave'

• status: Open
  
• priority: Major
  
• component(s): command-launcher-plugin
  
• resolution: Unresolved
  
• votes: 7
  
• watchers: 7
  
• imported: 20251215-193512
  

Raw content of original issue

We can start slaves via 'run a command on master' but shutting them down would be most convenient if a separate comand was run.

• environment: Using a VM for slaves.

The payload names only the command-launcher-plugin and its existing “run a command on master” behavior; no source file, entry point, or test is identified. Begin by locating that implementation and its tests, then define the shutdown command’s lifecycle and verify the behavior with focused plugin tests.

Written by the indexing model from the issue text.