SERVER-132123 Implement V3 explain support for express and SBE executors

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• Closed

SERVER-133607 Extend V3 explain with support for express executor

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• Needs Merge

SERVER-132079 Stop sourcing explain content from OpDebug diagnostics state

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• Needs Scheduling

SERVER-133811 SBE V3 explain omits queryPlanner.rankerChoice.reason because the ranking reason never reaches the explainer

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• Needs Scheduling

SERVER-134444 Deduplicate explain stop conditions and plan getter APIs once V3 support for SBE is finished

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• Needs Scheduling