Hoist key mutexes from every command impls to Connection::ExecuteCommand

[PragmaTwice]

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Motivation

We can remove all key-level mutex locking operations in command implementation and handle them uniformly in Connection::ExecuteCommand.

In this way, we can handle transaction support of scripts, index, etc. more easily.

Solution

No response

Are you willing to submit a PR?

• [ ] I'm willing to submit a PR!