Clean up IronCore repo

Summary

The IronCore repo currently ships in-tree broker implementations (broker/volumebroker,
broker/bucketbroker) and the VolumePool / BucketPool abstractions alongside the API
and poollets. This roadmap item tackles two separated parts:

1. Move out the broker implementations: relocate volumebroker and bucketbroker
   out of the IronCore repo into dedicated repos, so core owns the API and orchestration
   while the implementations live on their own.
2. Evolve the pool model: deprecate the VolumePool / BucketPool abstractions with a
   clear migration path.

---

Scope

In Scope

• Proposal: IEP describing the target structure and migration path for VolumePool / BucketPool evolution.
• Move out brokers: relocate volumebroker and bucketbroker out of the
  IronCore repo into dedicated repos.
• Evolve pools: deprecate the VolumePool / BucketPool abstractions

Out of Scope

• Machine pools / machinebroker (compute) is not part of this cleanup.

---

Responsible Areas

• Ironcore API
• Storage
• Documentation

---

Contributors

• @lukasfrank
• @exampleuser2

---

Acceptance Criteria

• Proposal

  • An IEP is written and accepted describing the target structure

• IaaS

  • volumebroker and bucketbroker implementations are relocated from broker/ into dedicated repos.
  • VolumePool / BucketPool abstractions are deprecated

---

Action Items

• Assign labels (e.g., area/ironcore-api, kind/design)
• Set milestone (e.g., H1/2025)
• Assign dependent sub-issues in each required area
• Assign an owner to the issue using the GitHub "Assignee" field
• List all contributors in the "Contributors" section above
• Add this issue to the Roadmap project board