Current behavior
• Expense Amount currency = Project currency.  
• Category currency field appears only when ‘This expense has a unit price’ is enabled.

Problem
• Projects are billed to clients in USD, while contractor (copywriter) expenses must be logged in UAH.  
• Copywriter fees vary from task to task, so we cannot use the Unit Price option.

Needed enhancement
• Add a Currency selector in an Expense Category even when Unit Price is disabled.  
• When that category is chosen, the Amount field should display the category currency regardless of the Project / Workspace currency.

Benefit
• Eliminates project duplicates, keeps reports clean, and shows true profitability.