[JENKINS-35393] Fix problems with Pipeline's Snippet Generator

Address issues with Snippet Generator, either in the core logic (mostly in workflow-cps and structs plugins), or in Describable implementations in core and assorted plugins which behave poorly with it.

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Originally reported by jglick, imported from: Fix problems with Pipeline's Snippet Generator

• status: Open
  
• priority: Minor
  
• component(s): structs-plugin, workflow-cps-plugin
  
• resolution: Unresolved
  
• votes: 4
  
• watchers: 5
  
• imported: 2025-12-07
  

Address issues with Snippet Generator, either in the core logic (mostly in workflow-cps and structs plugins), or in Describable implementations in core and assorted plugins which behave poorly with it.

The issue points to core logic in the workflow-cps and structs plugins and to Describable implementations in core and assorted plugins. Start by reviewing those areas to identify a specific Snippet Generator failure; done is not defined beyond addressing the problems found, so the scope must be clarified first.

Written by the indexing model from the issue text.