feat(BE-ExpenseApproval): add unit vice president approval step and permissions

internal/modules/expenses/controllers/expense.controller.go

@@ -233,6 +233,8 @@ func (u *ExpenseController) Approval(c *fiber.Ctx) error {
 		approvalType = "manager"
 	} else if strings.Contains(path, "/approvals/finance") {
 		approvalType = "finance"
+	} else if strings.Contains(path, "/approvals/unit-vice-president") {
+		approvalType = "unit-vice-president"
 	} else {
 		return fiber.NewError(fiber.StatusBadRequest, "Invalid approval path")
 	}