Merge Cloud changes back to master - #19755

Automatically merges the latest public Cloud branch changes back into master.

Summary by cubic

Improves auto-extending Redis locks so a custom TTL is respected and a transient extend failure no longer stops the extend loop.

• Allows AUTO_EXTEND locks to carry a custom ttl instead of always defaulting to the polling interval.
• Swallows transient extend errors so later extend attempts still run; the final unlock still surfaces a real loss of the lock.
• Stops scheduling further extends once the lock operation is stopped.
• Applies a 60s TTL to the SQS definition rebuild lock.
• Adds tests covering custom-TTL extend cadence and recovery after a failed extend.

^{Written for commit da01756. Summary will update on new commits.}