wallet-cli: Integrate ocap kernel

Ref: #8446

The Ocap Kernel should be integrated into the wallet CLI. We should loosely replicate the architecture in [`metamask-extension#rekm/agentmask`](https://github.com/MetaMask/metamask-extension/tree/rekm/agentmask), where the kernel runs in its own process and manages its own persistence, and communicates with the wallet via a kernel service bridge that calls into the wallet's root messenger to execute actions.

Start by reading the referenced issue #8446 and the linked MetaMask agentmask architecture. Map how the wallet CLI, the separately running Ocap Kernel, kernel-owned persistence, kernel service bridge, and wallet root messenger relate. Done means the kernel is integrated with the wallet CLI and can communicate through the described bridge to execute wallet actions.

Written by the indexing model from the issue text.