[arch] Integrate with day planner to schedule tasks

[caasion]

Similar to relying on obsidian tasks for the task management. I could also integrate date planner into holos so that users can schedule tasks in a timeline view appropriately when it is available.

Originally I thought of integrating my own timeline view, which I can still do, but I think I should also give users the option to use Day Planner as the timeline if they wish to, and if they have all their data there.