Support configuring Pipelines concurrency using Keue

Goals

Explore delegating the concurrency mechanisms using the Kueue project. It should be possible to use Kueue for handling concurrency and mainly queues

See https://redhat-internal.slack.com/archives/C08CTR5FENN/p1741526536726859?thread_ts=1741181686.648379&cid=C08CTR5FENN

When defining a queue using Kueue, one should mention what are the resource assigned to this queue. Workloads consume resource from the queue they belong to. by than it's possible to limit the amount of running pipelineruns.for achieving feature parity with PAC, for example, a cluster queue can be created for each Repository, all the pipeline runs belong to that Repository should be assigned (via label) to the respective queue, this let one control the number of a concurrent pipelines belong to the same repo. It can be even more flexible than that, a queue can be defined for each pipeline type, for example pre/post merge. Then we can control the amount of concurrent pipeliens for each pipeline type.

This is an exploration epics, so the idea is to do a POC about it.

Out of scope

• Shipping with OSP

Dependencies

Mainly Kueue. This also means we'll have to wait for Kueue to be GA in OCP for having this fully supported.

Assumptions

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Customer Considerations

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Documentation Considerations

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What does success look like?

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QE Contact

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Impact

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Related Architecture/Technical Documents

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Done Checklist

• Acceptance criteria are met
• Non-functional properties of the Feature have been validated (such as performance, resource, UX, security or privacy aspects)
• User Journey automation is delivered
• Support and SRE teams are provided with enough skills to support the feature in production environment