We want to leverage CBR for those cases where we think multiplanner will struggle. Initially that is defined to cases where multiplanner was not able to pick a plan after trial period. Use QueryPlanRankerMode knob to enable the feature. Specifically when set to "automaticCE". Work both for the classic and SBE multiplanners. Ignore subplanning.

Given the uncertainty we want to come up with a working logic that can be measured vs the current implementation. Do not worry about code quality. Just prototype. It is not going to be merged into master.