feat(rails): support for solid queue

[solnic]

This adds support for SolideQueue by simply adding its spec suite that makes sure our common ActiveJob integration works with SolidQueue, including distributed tracing.

We may follow up with SQ-specific features added in separate PR(s).

⚠️ this builds on top of #2947 which should be reviewed/merged first.

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Closes #2587

[cursor]

Cursor Bugbot has reviewed your changes and found 2 potential issues.

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[cursor]

Drain loop never terminates

Medium Severity

The drain loop only exits when the ready queue is empty and there are no rows in SolidQueue::ScheduledExecution. If scheduled rows exist but none are due yet (scheduled_at still in the future), dispatch_next_batch promotes nothing, claim returns an empty set, and the loop keeps spinning because scheduled rows remain.

 

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[cursor]

Drain swallows job exceptions

High Severity

Calling perform on claimed Solid Queue executions returns a result object and rescues job failures instead of re-raising. The shared ActiveJob harness examples expect drain to propagate the same exceptions as ActiveJob::Base.execute, including for expect { drain }.to raise_error cases.

 

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