Avoid recomputing PlanProperties redundently #19796

Is your feature request related to a problem or challenge?

• part of [EPIC] Improve query planning speed #19795

We are trying to make planning faster. One significant cost of planning Physical (ExecutionPlans) is the time spent computing PlanProperties

for example with this benchmark

cargo bench --profile=profiling  --bench sql_planner -- physical_plan_clickbench_q7

While reviewing #19462 from @askalt , we discussed the idea of optimizing certain parts of planning (for example ExecutionPlan::with_new_children) to avoid re-calculating the PlanProperties unecessairly)

See the conversation starting here #19462 (comment)

Describe the solution you'd like

I would like to find some way to avoid recomputing plan properties except when it is necessary

Describe alternatives you've considered

No response

Additional context

Somewhat blocked on

• type coercion error in clickbench50 query #19809