A lighter InsertPlan for single data point insertion scenario

It is very common to insert data point by point into a single time series. For this scenario, IoTDB's InsertPlan is very unfriendly: a large number of array objects need to be constructed.

I suggest adding a separate InsertPlan (and corresponding execution logic) for this scenario to improve performance.


The issue concerns IoTDB's InsertPlan for inserting one data point at a time into a single time series. Start by tracing the current InsertPlan construction and its execution logic, then compare the proposed path with the existing one. Done means a separate, lighter insertion path that reduces array-object construction and improves performance for this scenario.

Written by the indexing model from the issue text.