feat(3475): Add DISABLED state and stateChanger fields to pipeline model

[sagar1312]

Context

Screwdriver supports enabling and disabling individual jobs to prevent builds from being created or executed for those jobs. This is useful for temporarily pausing specific parts of a pipeline without removing them.

However, for large pipelines with many jobs, managing this at the job level becomes time-consuming and inefficient — each job must be disabled individually. There is currently no way to disable an entire pipeline in one action.

Additionally, pipelines currently only support three states: ACTIVE, INACTIVE (used for child pipelines managed by a config pipeline), and DELETING. There is no first-class concept of a user-initiated disabled state at the pipeline level.

Objective

• Add DISABLED to pipeline states (VALID_STATES_FOR_UPDATE restricts updates to ACTIVE/DISABLED)
• Add stateChanger, stateChangeTime, stateChangeMessage fields to pipeline model
• Add migration to add new columns to pipelines table
• Add/update tests for new state and fields

References

screwdriver-cd/screwdriver#3475

License

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