muster release v5.21.0

Added

• muster test: scenarios can run their instance in Kubernetes mode. pre_configuration.mode: kubernetes starts one envtest control plane per run from the binaries KUBEBUILDER_ASSETS points at, installs the CRDs from helm/muster-crds, applies the scenario’s mcp_servers and workflows as CRs into a namespace of its own and runs muster serve with kubernetes: true against it – informers, reconciler, boot pass and CR status the way an installation has them. A TCP proxy the harness owns sits between muster and the API server: apiserver.reachable_after keeps it closed for that long after the process started (the API server late at start) and test_set_apiserver_reachable: false|true cuts and restores it mid-run. test_patch_cr applies a merge patch to a CR (spec.suspended, labels, spec.auth.authorizationServer) so the reconciler is driven by real CR updates; test_get_cr reads a CR with the status muster wrote; test_set_mcpserver_labels and test_pin_mcpserver_authorization_server update the CR in this mode. muster test --mode filesystem|kubernetes runs one definition source; without KUBEBUILDER_ASSETS the Kubernetes-mode scenarios are reported as skipped with the reason, never as passed, and make test-envtest (the test-envtest CI job) runs them against envtest. Four scenarios reproduce bugs the filesystem-mode suite could not express: a suspended server is not started by the boot pass (fails on v5.19.6, #1216), a suspended remote server is stopped once and not on every resync tick (fails on v5.19.0, #1212), the boot pass and the reconciler’s first pass register a dozen CRs without an ERROR (fails on v5.19.8, #1222), and an API server unreachable at start is waited for instead of swapped for the filesystem client (fails on v5.7.18, #1143); two more cover a boot from CRs and an API server gone mid-run. (#1237)

Fixed

• muster test: the process test_restart_instance starts no longer dies when the restart step returns. It was bound to the step’s context, so a restart step with a timeout killed the new muster serve right after it had passed readiness and the next step found the connection reset.