When a spec fails against a live environment, its teardown
(AfterEach/JustAfterEach/DeferCleanup) tears down the very state needed
to debug the failure. --sleep-on-failure=<duration> pauses the suite the
moment a failure is identified - before any teardown runs - so the live
system can be inspected.

The pause hooks directly into the suite's existing failure-handling path
(runNode): when a node finishes with a failure, Ginkgo emits the failure
and then, if the flag is set, pauses right there. Only failures in setup
and subject nodes (It, Before*, BeforeSuite...) pause; failures in
teardown/cleanup or reporting nodes do not, since the system is already
being torn down at that point.

The pause is interruptible: pressing ^C (or any interrupt) ends the pause
early and the suite proceeds to run cleanup as usual rather than skipping
it.

This is a debugging aid for interactive, serial runs. Because Ginkgo's
parallelism is multi-process, a single failing spec cannot meaningfully
freeze the whole system, so combining --sleep-on-failure with -p/--procs
is rejected with a configuration error.

Adds unit (internal_integration) and CLI (integration) tests and docs.

Assisted-By: Claude Opus 4.8 <noreply@anthropic.com>
Signed-off-by: Enrique Llorente <ellorent@redhat.com>

-fd's RSpec-style hierarchical output assumes specs run serially in
declaration order. Combined with parallelism or randomization it
produces fragmented, hard-to-read output. Rather than refusing to
run, Ginkgo now overrides -p/-procs/-randomize-all when -fd is set,
runs serially in declaration order, and prints a notice explaining
what was overridden.