feat(job): lifecycle hooks, an app-wide failure hook, and a stored result

changelog.d/4483-job-lifecycle-hooks.added.md

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+- Background jobs gained lifecycle hooks. `beforePerform(data)` and `afterPerform(data, result)` run with `perform()`, under its timeout, and a throw from either fails the attempt. `onSuccess(result)` runs once the job is recorded as completed, and `onFailure(error, attempt, isFinal)` after each failed attempt, with `isFinal = true` when the job won't be tried again (including when a crashed worker's last attempt is reaped). Both are best-effort: a throw is logged and never changes the job's outcome. `set(jobsOnFailure = "component.path.method")` adds an app-wide failure hook, called with one struct (`jobId`, `jobClass`, `queue`, `attempt`, `maxRetries`, `isFinal`, `error`) as its `event` argument; job data is never passed to it. `perform()`'s return value is now stored in a new `wheels_jobs.result` column (added automatically): simple values as-is, anything else as JSON, cut short at 4000 bytes with a `...[truncated]` marker. ([#4483](https://github.com/wheels-dev/wheels/issues/4483))