merge aggregators in `src/storage/aggregator.xx` and `hybridse/src/vm/aggregator.h`

**Describe the feature you'd like**
There are two different places to implement the pre-aggregation logics for the `long window` feature. We should finally merge these in order to avoid code duplication.

The issue mentions merging aggregators in `src/storage/aggregator.xx` and `hybridse/src/vm/aggregator.h`. First, examine these two files to understand the pre-aggregation logic for the 'long window' feature. Look for overlapping code and design a unified implementation. Check for existing tests related to aggregators to ensure the merge does not break functionality. The goal is to eliminate duplication while maintaining the same behavior.

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