feat(project-currency): implement project-specific currency support

- Added a currency column to the projects table to allow different projects to use different currencies.
- Updated existing projects to default to 'USD' if no currency is set.
- Enhanced project finance controller to handle currency retrieval and updates.
- Introduced API endpoints for updating project currency with validation.
- Updated frontend components to display and manage project currency effectively.

worklenz-backend/src/routes/apis/project-finance-api-router.ts

@@ -14,6 +14,7 @@ projectFinanceApiRouter.get(
   safeControllerFunction(ProjectfinanceController.getTaskBreakdown)
 );
 projectFinanceApiRouter.put("/task/:task_id/fixed-cost", ProjectfinanceController.updateTaskFixedCost);
+projectFinanceApiRouter.put("/project/:project_id/currency", ProjectfinanceController.updateProjectCurrency);
 projectFinanceApiRouter.get("/project/:project_id/export", ProjectfinanceController.exportFinanceData);
 
 export default projectFinanceApiRouter;