Invoices

🚧 Coming in COGS Phase 4

This is a placeholder for the Invoices list page. It will display all invoices with COGS and profitability data.

Required for implementation:

• API endpoint: GET /api/invoices (with COGS fields)
• Invoice data table component
• COGS columns: totalCOGS, grossProfit, grossMarginPercentage
• Access control for cost visibility
• Link to invoice detail page