## Story 004: View this week's and all-time session statistics

**Persona:** Elena, 31, writer. Obsessive about tracking her productivity over time. Uses session data to understand her patterns — which days she focuses best, how her output has improved over months.

**Situation:**

Elena has been using Pomodoro for six months. She opens the app on Sunday evening to see her weekly total and compare it to last week. She also checks her all-time stats to feel the arc of her progress.

**Need:**

As Elena, I want to see how many sessions I completed this week and in total across all time, so that I can track my focus capacity and celebrate the progress I'm making.

**Acceptance:**
- The History tab shows three views: 'Today', 'This Week', 'All-Time'
- Today's view shows session count and list (as per prior story)
- This Week's view shows total sessions and total focus time for the current week (Mon–Sun or Sun–Sat, configurable)
- All-Time view shows total sessions ever and total focus time ever; optionally, a graph or timeline showing weekly averages over the past 12 weeks
- The app persists this data across app restarts

**Tier:** core

**Confusion-flags:**
- How many weeks of history should be shown in the 'All-Time' graph? Should it be interactive (e.g., scroll back to see older weeks)? The directive doesn't specify depth of historical UI.
- Should the app show streaks (consecutive days with at least N sessions) or other habit-tracking metrics? That feels like enrichment, but I'm not certain where the line is.
