feat(finance): expose Form 990 line catalog endpoint

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

API/ROLAC.API/Controllers/Form990ReportController.cs

@@ -12,6 +12,9 @@ public class Form990ReportController : ControllerBase
     private readonly IForm990ReportService _svc;
     public Form990ReportController(IForm990ReportService svc) => _svc = svc;
 
+    [HttpGet("lines")]
+    public async Task<IActionResult> Lines() => Ok(await _svc.GetLinesAsync());
+
     [HttpGet("functional-expenses")]
     public async Task<IActionResult> FunctionalExpenses([FromQuery] DateOnly? from, [FromQuery] DateOnly? to)
         => Ok(await _svc.GetFunctionalExpenseStatementAsync(from, to));

API/ROLAC.API/DTOs/Finance/Form990ReportDtos.cs

@@ -23,3 +23,13 @@ public class FunctionalExpenseStatementDto
     /// <summary>Expenses with no explicit 990 mapping (counted under line 24). Prompts mapping cleanup.</summary>
     public int     UnmappedExpenseCount   { get; set; }
 }
+
+/// <summary>A single IRS Form 990 expense line from the catalog (used to populate mapping dropdowns).</summary>
+public class Form990ExpenseLineDto
+{
+    public int     Id        { get; set; }
+    public string  LineCode  { get; set; } = "";
+    public string  Name_en   { get; set; } = "";
+    public string? Name_zh   { get; set; }
+    public int     SortOrder { get; set; }
+}

API/ROLAC.API/Services/Form990ReportService.cs

@@ -15,6 +15,19 @@ public class Form990ReportService : IForm990ReportService
     private readonly AppDbContext _db;
     public Form990ReportService(AppDbContext db) => _db = db;
 
+    public async Task<List<Form990ExpenseLineDto>> GetLinesAsync() =>
+        await _db.Form990ExpenseLines.AsNoTracking().Where(l => l.IsActive)
+            .OrderBy(l => l.SortOrder)
+            .Select(l => new Form990ExpenseLineDto
+            {
+                Id        = l.Id,
+                LineCode  = l.LineCode,
+                Name_en   = l.Name_en,
+                Name_zh   = l.Name_zh,
+                SortOrder = l.SortOrder,
+            })
+            .ToListAsync();
+
     public async Task<FunctionalExpenseStatementDto> GetFunctionalExpenseStatementAsync(DateOnly? from, DateOnly? to)
     {
         var lines = await _db.Form990ExpenseLines.AsNoTracking()

API/ROLAC.API/Services/IForm990ReportService.cs

@@ -4,4 +4,5 @@ namespace ROLAC.API.Services;
 public interface IForm990ReportService
 {
     Task<FunctionalExpenseStatementDto> GetFunctionalExpenseStatementAsync(DateOnly? from, DateOnly? to);
+    Task<List<Form990ExpenseLineDto>> GetLinesAsync();
 }