feat: give listeners the same output channel as tasks

[refsz]

Same content as #31, retargeted at main. #31 is marked merged, but its base was feature/argv-exec, and that branch had already been squash-merged into main as #30 — so the commit landed on a branch that no longer leads anywhere and src/Console/OutputChannel.php is absent from main. This is the identical commit cherry-picked onto current main; nothing was rewritten. My mistake for stacking the PR instead of waiting for #30 to land.

---

A listener that ran a command produced nothing at all. Not truncated, not unformatted — silent.

There were two executor paths, and only one had an output:

Caller	Executor	Output
Task	TaskRunner::createContext() built new ShellExecutor($output)	visible
Listener	the container's shellExecutor service, built with no arguments	discarded

The evidence is the consumer count: @shellExecutor was referenced in exactly one place in the codebase — as the inner of the listener executor. That service existed only for listeners, and it was the one without a destination. A composer install in a listener ran silently for minutes, a failure went unreported, and listeners in the field fell back to echo, which bypasses the redacting output and can print a secret.

One place that knows where Sputnik writes

Console\OutputChannel is registered empty, filled once bin/sputnik has wrapped the output in the redacting decorator, and shared from there:

bin/sputnik → OutputChannel ← ShellExecutor (one instance, tasks and listeners)
                           ← TaskRunner (adds the per-run SputnikOutput)
                           ← listeners (inject it to write)

ShellExecutor takes the channel instead of two nullable output parameters, and TaskRunner no longer constructs its own executor but takes the container's. That removes the second path rather than giving it an output too.

Filling the channel at startup, not in TaskRunner::run(), is what matters for the case this started from: context:switch is a command, not a task, so its listeners never pass through the task runner — which is exactly where the reference project's reset-on-switch listener lives.

Listeners can now write properly:

public function __construct(private readonly OutputChannel $output) {}

public function __invoke(ContextSwitchedEvent $event): void
{
    $this->output->writeln('Switched to ' . $event->newContext);
}

Deliberately not included: variables, templates or task execution for listeners. The missing output channel is a defect with evidence; the rest has no case yet.

Verification on top of current main

vendor/bin/phpunit          742 tests, 1281 assertions, OK
vendor/bin/phpstan analyse  [OK] No errors
vendor/bin/php-cs-fixer     0 of 153 files
vendor/bin/rector --dry-run [OK]

The proof is an end-to-end test driving the real binary through context:switch with a listener running echo, asserting the output appears. It is discriminating: removing the single line that fills the channel makes it fail, verified by mutation.

🤖 Generated with Claude Code

https://claude.ai/code/session_018CTvnzcNYmFgm2HQcm821A