Improve cli help docs for dev purge and dev reset commands

[steezeburger]

I think we can rewrite the descriptions to be informative.

We should answer these questions:

• what exactly does purge delete?
  • can probably just add to existing help, something like: "Delete all data for a given instance. This includes chain state, configuration, and the service binaries. ..."
• what does "reset config files" mean exactly?
  • I think it means to reset the config files to their default values, but we can make this more clear in the help text.
  • something like: "Reset base config file to default values. ...:
• what does it mean to "reset the networks config? exactly?
  • again, I think it means to reset the config files to their default values, since a user may have updated a value here
  • "Reset network config file to default values. ..."
• what does it mean to "reset sequencer state"?
  • I think this one means to delete cometbft and sequencer data
  • something like: "Reset Sequencer chain state to initial state. ..."

┆Issue Number: ENG-695