[Aubaid12]

Part of #398

Problem

civo kubernetes create has no limit on positional args, so civo kubernetes create test2 test3 test4 creates a single cluster called test2 and silently drops the other names.

Fix

• Added Args: cobra.MaximumNArgs(1). The name is still optional (a random one is generated when it's missing), but passing more than one now fails before any API call.
• Changed Use to create [CLUSTER_NAME] so the usage line shows the optional name, the same way instance create does.

$ civo kubernetes create test2 test3 test4
Error: accepts at most 1 arg(s), received 3
Usage:
  civo kubernetes create [CLUSTER_NAME] [flags]

The issue mentioned either creating them all or failing. I went with failing, since size, nodes, network and firewall apply per cluster and creating several clusters from one call would be easy to do by accident. Same approach as #602.

This does change behaviour for anything that passed stray args before, for example an unquoted name with a space (civo k8s create my cluster used to create my). It errors now instead.

Tests

• Table-driven TestKubernetesCreateArgs in cmd/kubernetes/kubernetes_create_test.go (no name, one name, extra names)
• Checked against a local stub API: with three names, master sends one create request for test2. With this change there are no API calls, and flags mixed between names (create a --nodes 2 b) are rejected too. One name and no name send the same requests as before.
• go test ./... and golangci-lint pass locally

Some other create commands have the same gap. instance create has no Args check, and a few that use MinimumNArgs(1) (e.g. volume create) also ignore extra names. I can look at those in a separate PR if you want.

[fulviodenza]

Thanks for this. Reviewed: cobra.MaximumNArgs(1) still allows zero args, so the random cluster name path is unchanged, and the pattern matches the existing objectstore credential secret command. The test exercises the real command's arg validation. I updated the branch from master so CI ran against current dependencies (the earlier govulncheck failure was x/net on the stale base), and Lint, Security and Test are now green.

Small follow-up for later, not blocking: kubernetesCreateCmdExample still shows civo kubernetes create CLUSTER_NAME [flags], which reads as required now that Use says [CLUSTER_NAME].