Update yahcli `staking` to auto-create staking accounts in dev environments

### Problem

When resetting previewnet or testnet, we want to automatically re-enable staking and ensure all nodes have min-stake.

### Solution

Add a `staking post-reset-setup` subcommand.

### Alternatives

_No response_

Start by locating the yahcli implementation of the existing staking commands and the reset flow used for previewnet or testnet. Add the `staking post-reset-setup` entry point, then verify that a reset re-enables staking and ensures every node has min-stake.

Written by the indexing model from the issue text.