[JENKINS-75343] Add option to filter org folder repositories by custom property

GitHub's custom properties were rolled out in 2024 as another way to categorize repositories with attributes. Having an org folder filter by custom property value would be similar to filtering by topic, but could be safer for multi-tenant environments. While a repository may have multiple topics monitored by separate org folders (inadvertently picked up in multiple places), matching by a specific custom property value `jenkins: instance-acme` can be more explicit.

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Originally reported by pwalkr_asc, imported from: Add option to filter org folder repositories by custom property

• status: Open
  
• priority: Minor
  
• component(s): github-branch-source-plugin
  
• resolution: Unresolved
  
• votes: 0
  
• watchers: 1
  
• imported: 2025-12-02
  

GitHub's custom properties were rolled out in 2024 as another way to categorize repositories with attributes. Having an org folder filter by custom property value would be similar to filtering by topic, but could be safer for multi-tenant environments. While a repository may have multiple topics monitored by separate org folders (inadvertently picked up in multiple places), matching by a specific custom property value `jenkins: instance-acme` can be more explicit.