Blockchain storage architecture and metadata

[6r1d]

After yesterday's community discussion and #318, I am trying to understand how Metadata implementation is stored in Kura, compared to Store assets.

Does each change in metadata create some record in the blockchain with an update, making the read performance similar and reducing it in cases of large Metadata contents?

The approach to performance here is worth documenting to explain to the users when Store assets are preferable, at least in my opinion.

[6r1d]

As confirmed by @appetrosyan, both Store and metadata modifications are stored as blockchain records, thus the retrieval speed is only worse for metadata in certain cases.

[nxsaken]

Contained in #450 and #451.