Implement Active State for Invoice and Contract Payment Detail Screens [Flutter] #55
Description
Extend the Invoice and Contract Payment detail screens to handle the active/confirmed state where the status badge shows "Online" or "Contract" and more timeline steps are completed. The timeline progresses further showing steps like "Client payment confirmed", "Processing your client payment", and balance update notifications. Ensure the timeline scrolls if content overflows and that completed steps visually differ from pending ones. This is the mid-flow state after a client has confirmed payment but before funds are fully received.
Acceptance Criteria:
- Status badge updates to reflect the active/confirmed state (e.g., "Online", "Contract")
- Timeline renders additional completed steps with green indicators and timestamps
- Steps such as "Client payment confirmed" and "Processing your client payment" display correctly
- Pending steps below the current progress remain outlined/muted
- Timeline is scrollable when content exceeds screen height
- All fields (Contract, Invoice, Client, Network) remain visible in the header section
- Layout is consistent with the base detail screen from Task 2