Reduce pipelines processing latencies

[r4victor]

Closes #3808

Remove artificial processing latencies in core pipelines. Add skip_min_processing_interval field for JobModel, RunModel, InstanceModel that allows skipping pipelines' min_processing_interval.

Improvements:

• Up to 14s for run dstack apply (from submit to running), e.g. running on an idle instance with a pulled image is 10-15s (from 25-30s).
• Up to 7s for runs stop (from stop to terminated).
• Up to 7s for instance termination after job termination.
• Up to 7s for instance termination after fleet/instance delete.