[feature]: add `ksail cluster update` for in-place updating a cluster

[devantler]

User Story

As a KSail user,
I want a ksail cluster update command that reconciles a running cluster with the current KSail configuration,
So that I can safely apply config changes (including node scaling) without manually recreating or re-provisioning the cluster.

Acceptance Criteria

• Command: ksail cluster update exists under ksail cluster and uses the same config loading behavior as other cluster commands.
• In-place update: If the active distribution/provider supports in-place updates, the command applies changes without recreating the cluster.
• Node scaling: If the desired node counts differ from the running cluster, ksail cluster update scales nodes when supported; otherwise it offers a recreate flow.
• Recreate prompt: When changes require recreation (e.g., update/scale not supported), the CLI prompts the user and only proceeds if they type exactly yes.
• Force flag: --force skips the confirmation prompt and recreates the cluster directly.
• Safety: If the user does not type yes (and --force is not set), the command exits without changing the cluster.
• Recreate behavior: Recreate performs delete + create and runs the same post-creation setup as ksail cluster create (CNI + post-CNI components).
• Provider/distro matrix: Unsupported combos do not silently no-op; they either update/scale, or require explicit user confirmation to recreate.