Use TPU for creating accounts

Currently, for the speed of development primarily, we create accounts using RPC. It would be faster creating them using TPU transactions.

Start by locating the account-creation entry point and the current RPC call. Read the repository's TPU transaction interfaces and determine how this flow should use them without changing account-creation behavior. Done means accounts are created through TPU transactions and the relevant existing checks still pass.

索引モデルが issue の本文から書いたものです。