Krikri::PluginHelpers::AnsibleSplitlines

AnsibleSplitlines - pure logic matching real Ansible's stdout_lines/stderr_lines derivation, which is built from Python's str.splitlines(), not Crystal's plain String#split("\n"). The two differ on exactly the cases that matter for real command output: empty input - Python's splitlines() gives [], Crystal's split gives [""] (one empty element) - and any trailing newline, which split() turns into a spurious final empty element that splitlines() never produces. Found via konstruktoid-hardening's "Delete unmanaged UFW rules" task: its ufw_not_managed command's grep -v legitimately matches nothing (every rule this role adds is tagged "ansible managed" and filtered out), producing empty stdout; ufw_not_managed.stdout_lines | length > 0 should then gate the whole loop off, but the spurious [""] made it loop once with an empty item, running ufw delete with no rule spec at all - which real ufw rejects with "ERROR: Invalid syntax".

Shared by the plugins that produce stdout/stderr (command, shell - each module that has stdout/stderr sets the *_lines keys itself in real Ansible) AND TaskExecutor's register augmentation (which derives them centrally for results that predate a plugin carrying its own).