Add a daily performance summary report for merchants

[StuartFerguson]

Summary

Add a mobile-friendly daily performance summary report so merchants can quickly see how their business is performing without needing to drill into raw transaction history.

User Value

Merchants need a fast way to answer:

• How many transactions have I processed?
• What is my total value today?
• How many succeeded or failed?
• Which product or operator is performing best?

Scope

Create a report screen that shows summary metrics for:

• Today
• Yesterday
• This week
• Month to date
• Custom date range if supported by the host

Suggested metrics:

• Total transaction count
• Successful transaction count
• Failed transaction count
• Reversed / voided transaction count if available
• Total transaction value
• Average transaction value
• Top product or operator

Mobile UX Requirements

• Use summary cards at the top of the screen.
• Avoid dense tables on the main view.
• Keep the default view focused on the current day.
• Allow drill-down into a limited list of underlying transactions if needed.
• Ensure the layout remains readable on a small phone screen.

Acceptance Criteria

• Merchant can view a daily summary report from the app.
• Merchant can switch between at least today, yesterday, and this week.
• Metrics are displayed clearly in a mobile-friendly layout.
• The report handles empty states gracefully.
• The report handles host or network failures with a clear message.

Notes

This should reuse existing reporting navigation patterns where possible.