Premium statistics #154

Description

Extend the statistics screen to display premium statistics for subscribed users. When the user is a premium subscriber, the premium-upsell section from #151 is replaced with the premium statistics section.

Premium statistics include:

• Completion rate (percentage of tasks completed vs created over a period)
• Average tasks completed per day over the last 7 days
• Most productive day of the week
• Tasks completed by priority breakdown

This ticket also removes the premium-upsell CTA for premium users since they already have access.

Depends on #150 (Statistics data layer), #151 (Free statistics screen), #130 (Premium gating infrastructure).

Scope

In scope: displaying premium statistics on the Statistics screen, replacing the upsell section for premium users, completion rate, average tasks per day, most productive day, priority breakdown, and string resources.

Out of scope: statistics data layer computation (#150), free statistics screen (#151), paywall UI.

Acceptance criteria

• GIVEN the user is a premium subscriber and is on the Statistics screen
  WHEN the screen renders
  THEN the premium-upsell section is replaced with a premium statistics section showing completion rate, average tasks completed per day, most productive day of the week, and tasks completed by priority breakdown
• GIVEN the user is a premium subscriber
  WHEN the Statistics screen renders
  THEN no premium-upsell CTA is shown
• GIVEN the user is not a premium subscriber
  WHEN the Statistics screen renders
  THEN the premium-upsell section remains visible (no changes from Free statistics screen #151)
• GIVEN the completion rate is computed
  WHEN it is displayed
  THEN it shows the percentage of tasks completed vs created over the selected period
• GIVEN average tasks completed per day is computed
  WHEN it is displayed
  THEN it shows the average number of tasks completed per day over the last 7 days
• GIVEN most productive day of the week is computed
  WHEN it is displayed
  THEN it shows the day of the week with the highest number of tasks completed
• GIVEN tasks completed by priority breakdown is computed
  WHEN it is displayed
  THEN it shows the count of completed tasks grouped by priority level (High, Medium, Low)
• GIVEN user-visible text appears on the premium statistics section
  WHEN the app renders it
  THEN all visible text comes from string resources