Add logic to populate new destinations when pipeline is created

Problem

When a pipeline is created we need to create ci_job_definitions records taking in consideration race conditions at project-level.

Proposal

• Use Draft: PoC: split build metadata into `job_prot... (!193948 - closed) as inspiration for the work to do.
• We may need to persist job definitions in bulk and take in consideration race conditions on multiple jobs of the same definition being created for the first time.
  • See !193948 (comment 2587555469) for more details on how to approach this.
  • This can be particularly frequent when creating a new partition and may concurrent pipelines will race to create the first definition of the partition.
• Ensure persisted environments are stored as direct association with ci_builds and intrinsic data about environments stored in there action, deployment_tier, kubernetes.namespace).
• Use a feature flag write_to_new_ci_destinations - the PoC used a feature flag write_to_ci_job_prototypes