Enable Data Blocks Caching

Currently, Magma does not cache data blocks by default due to the fact the KV has its own document caching. For BHIVE, it does not have its own cache, so we will need to enable data block caching in Magma as a setting, or alternatively BHIVE to build its own vector cache. We also need to be able to calculate RR including data blocks (not just on the index blocks).

We need to introduce a new optional config flag to enable caching data blocks from bySeqIndex. Necessary stats needs to be introduced to report the aggregate resident ratio for index+data blocks.