Use when the user wants to bind a Unit (or many Units) to a destination — a specific Kubernetes cluster+namespace, an ArgoCD Application, a Flux Kustomization, an OCI registry, a Tofu workspace. Phrases like "set up a target", "point this unit at my cluster", "bind these units to prod", "hook up Argo/Flux", "change the namespace this deploys to", "promote these to a different target". Creates or updates a Target with the right provider/toolchain and parameter JSON, attaches Units via cub unit set-target (or --where for bulk), and stops without applying — apply is cub-apply's job. Do not load for installing a worker (use worker-bootstrap first — Targets reference Workers), for running apply (use cub-apply), or for authoring the Unit's YAML (use config-as-data).