SERVER-116178 Add resmoke passthrough that loads $vectorSearch extension

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• In Progress

SERVER-115789 Enable nested $unionWiths to use 'from: view' and 'pipeline: $extensionStage'

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• Closed

SERVER-115790 Enable $unionWith+extension as part of a view definition

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• Closed

SERVER-117169 Make sure extension tracking counts sub-pipelines correctly

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• In Code Review

SERVER-117662 Test extension stages in nested hybrid search stages

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• Backlog