title: Add `ClaimQueue` wrapper

doc:
  - audience: Node Dev
    description: |
      Intoduces a new wrapper type: `ClaimQueueSnapshot`. It contains a snapshot of the `ClaimQueue`
      at an arbitrary relay chain block. Two methods are exposed to allow access to the claims at 
      specific depths.

crates:
 - name: polkadot-node-subsystem-util
   bump: minor