[feature]: Support segmented/multiple date ranges for interrupted work items

Is there an existing issue for this? • I have searched the existing issues Summary Problem Plane currently supports only a single continuous date range (one start date + one end/target date) per work item. This breaks down when a task is paused mid-flight and resumed later, which is a very common pattern on teams that enforce a "one task in progress at a time" rule. Real-world scenario 1. May 15 — I start Task A (low priority, ~1 week of work). Status: In Progress. 2. May 17 — Task B comes in (high priority, urgent). Team policy: only one task can be In Progress at a time. 3. Team lead freezes Task A and moves Task B to In Progress with dates May 17 – May 20. 4. May 20 — Task B is done. I resume Task A. Now I'm stuck choosing between two bad options for Task A's dates: • Keep May 15 – May 20: It looks like Task A was worked on continuously, hiding the 3-day pause. Time tracking, burndown, and analytics are wrong. • Change to May 20 – May 2…