Summary

Adds an optional Queue.workerLifetimeJitter config (seconds). Each worker picks a random offset in [0, workerLifetimeJitter] at startup and adds it to its effective workerLifetime / --max-runtime. When a fleet of workers is spawned at the same instant (ECS tasks, Kubernetes deployments, systemd unit with many instances), this prevents every worker from terminating on the same tick and producing a thundering-herd of simultaneous restarts.

Defaults to 0, so behavior is unchanged unless the option is set.

// config/app.php
$config['Queue']['workerLifetime'] = 300;
$config['Queue']['workerLifetimeJitter'] = 30; // workers now exit between 300s and 330s

Credit

Idea and original implementation by Rommel Penaflor (@xrompdev) in #475, where it was proposed against a legacy CakePHP 2.x Symphosize fork and therefore could not be merged directly. This PR is a fresh port to the modern Queue\Queue\Processor, keeping the operational intent intact.

Implementation notes

• Jitter is computed once per worker (right after $startTime = time() in Processor::run()), not re-rolled each loop iteration, so the exit time is stable per worker.
• Extracted into Processor::computeLifetimeJitterOffset() so the bounds/default behavior is unit-testable without spinning up the full run loop.
• Only applied when $maxRuntime > 0 — unlimited workers stay unlimited.
• <= 0 jitter values are ignored (returns 0), so a misconfigured negative value is a no-op rather than an error.
• If jitter was applied, the worker logs Applying worker lifetime jitter: +Ns seconds so operators can see the stagger in action.

Docs

Added a dedicated bullet in docs/sections/configuration.md directly after the workerLifetime section, explaining the ECS/K8s use case.