Enhance `Volume` Resize

[lukasfrank]

Summary

Currently, Volume resources support resizing via the spec.size field, but there is no corresponding status field to reflect the actual allocated size. This makes it difficult to determine whether a resize operation was successfully completed or not, leading to operational uncertainty and complicating automation.

Tasks

• [ ] Update volume-IRI, volume-poolet and volume-broker to reflect size in Status
• [ ] Provide concept to indicate that a Volume attached to a Machine should be resized
  • [ ] If changes in machine-IRI, machine-poolet and machine-broker are needed provide proposal
  • [ ] Implement changes