update detail.

API/ROLAC.API/Services/Form990ReportService.cs

@@ -8,7 +8,7 @@ namespace ROLAC.API.Services;
 /// <summary>
 /// Read-only aggregation that produces the IRS Form 990 Part IX Statement of Functional
 /// Expenses. Expense scope matches FinanceDashboardService: Paid + Approved only.
-/// Single function per expense (direct-charge); no cost splitting.
+/// Each expense line is categorized independently, so one invoice can span multiple lines.
 /// </summary>
 public class Form990ReportService : IForm990ReportService
 {
@@ -40,13 +40,14 @@ public class Form990ReportService : IForm990ReportService
 
         var rows = await (
             from e in expenses
+            join l   in _db.ExpenseLines           on e.Id              equals l.ExpenseId
             join m   in _db.Ministries            on e.MinistryId      equals m.Id
-            join sub in _db.ExpenseSubCategories   on e.SubCategoryId   equals sub.Id
-            join grp in _db.ExpenseCategoryGroups  on e.CategoryGroupId equals grp.Id
+            join sub in _db.ExpenseSubCategories   on l.SubCategoryId   equals sub.Id
+            join grp in _db.ExpenseCategoryGroups  on l.CategoryGroupId equals grp.Id
             select new
             {
-                e.Amount,
-                e.FunctionalClass,
+                l.Amount,
+                l.FunctionalClass,
                 MinistryDefault = m.DefaultFunctionalClass,
                 SubLineId   = sub.Form990LineId,
                 GroupLineId = grp.Form990LineId,