apps: cover the genpkey error cases and verbose mode in the test recipe

Cover the bad option failures (missing algorithm, extra arguments,
invalid output format, unknown algorithm, key option, cipher and
password arguments) as well as the failures when loading a
nonexistent or invalid parameters file, verifying the error messages
printed to stderr.  Also cover the -verbose progress output and the
-quiet option.

Assisted-by: Claude:claude-fable-5
Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
Reviewed-by: Tomas Mraz <tomas@openssl.foundation>
Merge-date: Mon Sep  7 14:15:52 2026
Merged-from: https://github.com/openssl/openssl/pull/32592