feat: execute auto-scaling in batches

[shanicky]

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What's changed and what's your intention?

This PR adds 3 parameters for fine-tuning the monitor loop once auto-scaling is enabled.

parallelism_control_batch_size = 10
parallelism_control_trigger_period_sec = 10
parallelism_control_trigger_first_delay_sec = 30

The parallelism_control_batch_size parameter is used to determine how many streaming jobs are processed each time auto-scaling is enabled. When set to 0, it will be configured to handle all jobs.

The parallelism_control_trigger_period_sec parameter determines the period for triggering auto-scaling, with the default set to every 10 seconds.

The parallelism_control_trigger_first_delay_sec parameter is used to determine the delay before the first scale-out to avoid unnecessary conflicts with recovery. It will be deprecated after the stream manager and barrier manager are merged.

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• All checks passed in ./risedev check (or alias, ./risedev c)

[yezizp2012]

Reset LGTM, This PR is to solve the problem that the memory overhead during barrier mutation decode in the auto scaling process may cause cn OOM. See details in #14533 , I'm rising a PR to fix it right now.