Self-hosted Kura cache nodes with per-account mesh enrollment

Customers can now run Kura cache nodes in their own infrastructure (for locality or data residency) alongside their Tuist-managed cache. From the account’s Cache page you can issue a per-account self-hosted client credential, and any node you spin up with that credential and a URL self-registers, enrolls in your account’s mesh via a controller-managed per-account peer CA, and joins the same mutually-authenticated mesh as your managed pods. Writes on a self-hosted node replicate into the shared managed cache, and the node warms from the managed cache when it joins; nodes stay outbound-only and no inbound connection is needed.