agent modules: Persist agentic chat sessions across workspace restarts

[stirby]

Depends on #31.

Once we add/switch to tmux for the agentic modules, we should allow chat sessions to persist across workspace restarts using tmux-resurrect and tmux-continuum.

...In our claude-code and goose modules.

[bpmct]

One other idea is to do this via memory: #127

[bpmct]

Regardless, the product requirement is:

• I want to be able to restart my workspace and it is aware of my AI agent progress and continues. Today, this is not the case and it attempts to start from the beginning and is only aware of the task prompt