fix(cli): delete honors --kubeconfig/--context; clears active-client pointer under --keep-data

[saadqbal]

Resolves both Cursor Bugbot findings on the develop→main PR #164.

High — delete ignored --kubeconfig/--context

tracebloc delete registered --kubeconfig/--context but runDelete never read them, so helm uninstall ran against the ambient current-context. An operator whose current context isn't the local tracebloc cluster could uninstall the wrong release.

• nodeboot.UninstallChart now takes kubeconfig + kubeContext and appends --kubeconfig / --kube-context to the helm call (only when non-empty, so default-context behavior is unchanged).
• runDelete threads o.kubeconfigPath / o.contextOverride through.
• k3d cluster delete targets the cluster by name, so it's context-independent — no change needed there.

Medium — --keep-data left a dangling active-client pointer

Under --keep-data, offboard revoked the credential but left the active-client pointer in ~/.tracebloc, so a later sign-in / reinstall still treated the host as enrolled as the (now-revoked) client.

• Clear ActiveClientID/Name/Namespace even under --keep-data; the token and on-host datasets stay, and re-running client create re-adopts by cluster_id (§7.5 principle: a dead credential must not leave a live-looking pointer).

Tests

• unit: --kubeconfig/--kube-context appear in the helm args.
• delete-level: the flags reach the uninstall seam; --keep-data clears the pointer while sparing the data dir.
• go build/vet/test ./... green (11 pkgs).

Once merged to develop, #164 (develop→main) picks these up. Rolls up under the §7.10 offboarding work (no separate ticket — Bugbot follow-up).

🤖 Generated with Claude Code

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Note

Medium Risk
Changes offboarding teardown (Helm cluster selection) and local enrollment state after revoke; mistakes could uninstall the wrong release or confuse reinstall, but scope is limited to the delete path with new tests.

Overview
Helm uninstall targeting — runDelete forwards --kubeconfig and --context into nodeboot.UninstallChart, which adds --kubeconfig / --kube-context to helm uninstall when set so offboard hits the intended cluster instead of the ambient current-context.

--keep-data enrollment state — After revoke, offboard still clears ActiveClientID, ActiveClientName, and ActiveClientNamespace in config and saves, while leaving ~/.tracebloc on disk so later client create can re-adopt without the host looking still enrolled.

Tests cover Helm args, delete-level flag threading, and active-client clearing under --keep-data.

^{Reviewed by Cursor Bugbot for commit 6ced546. Bugbot is set up for automated code reviews on this repo. Configure here.}