Add `barqinspect` Command for Payment Inspection

Currently, we have a `barqrouteinfo` command that simulates a payment and returns the potential route that `barq` could take if `barqpay` is executed.

We propose adding a new command, `barqinspect`. This command will allow users to inspect a specific payment from the history using its ID. It should provide details about whether the payment completed successfully or failed, along with the associated logs.

This feature is dependent on implementing a storage solution (#7).

Review the existing `barqrouteinfo` command and the storage solution tracked in issue #7 before starting. Define how `barqinspect` looks up a payment by ID, reports success or failure, and presents its associated logs; done means the command can inspect stored payment history reliably.

Written by the indexing model from the issue text.