Let me mark tasks as in progress

[robert-crandall]

Problem

I can mark tasks Done, but I cannot distinguish work I've started from work I haven't started. I want to see what I'm already working on when choosing my next task.

Expected behavior

• Let me manually mark a task In progress, return it to To do, or mark it Done.
• Show the in-progress state in the task list and task details.
• Preserve that state across collection, assessment, ranking, profile switches and app restarts, within the task's work profile.

This is local task state, not a change to the GitHub issue or a signal to start a Copilot session.