Deploy self-hosted Kura cache nodes bridged to the managed mesh

Enterprise accounts can now run their own Kura cache nodes inside their own infrastructure while staying connected to the same mutually authenticated mesh as Tuist-managed nodes. Each account gets its own certificate authority, and self-hosted nodes enroll via tenant-scoped credentials and heartbeats, so writes from your runners replicate into the shared managed cache and the node warms from the cache on join. This gives customers control over locality and data residency without sacrificing the benefits of the managed mesh.