[Open beta] Container image and tag deletion now available in Bitbucket Packages

Introduces container image and tag deletion capabilities for Bitbucket Packages, enabling users to remove outdated or unused images and tags. Implements automated background garbage collection to reclaim storage space by deleting unreferenced blobs. Details the process for deleting individual tags and entire container images, including required permissions. Prepares for the upcoming general availability release (December 3, 2025) by outlining the consumption-based billing model for storage and network traffic, including overage charges.