Custom storage prototype (with proper alignment)

[gz]

• Build storage prototype that repurposes the LSM /DRAM spine implementation and stores columnar data in a custom rkyv friendly format which allows for 0-copy deserialization
• Evaluate it by running a subset of (slow) nexmark queries

This will establish a better upper bound on what we could get from something (not rocksdb) that doesn't have the issue with alignment and isn't bogged down by column families

[blp]

A big part of the storage prototype is ready for review: https://github.com/feldera/feldera/pull/1250

[mihaibudiu]

the emphasis here is on the word "big"

[blp]

PR #1250 was merged.