feat: complete legacy parity and modernize operator UI

tests/MBN_STOCK_WEBVIEW.LegacyApplication.Tests/TradingHalt/LegacyTradingHaltWorkflowTests.cs

@@ -13,6 +13,27 @@ public sealed class LegacyTradingHaltWorkflowTests
     private static readonly TradingHaltSelection KosdaqAlpha =
         new(TradingHaltMarket.Kosdaq, "035720", "다온테크");
 
+    [Fact]
+    public async Task Search_AutomaticallyActivatesFirstFarPointRowAndActions()
+    {
+        var service = new DelegateTradingHaltService
+        {
+            Search = (query, _, _) => Task.FromResult(
+                SearchResult(query, KospiAlpha, KospiBeta, KosdaqAlpha))
+        };
+        var controller = new LegacyTradingHaltWorkflowController(service);
+
+        var searched = await controller.SearchAsync(string.Empty);
+        var current = controller.MaterializeSelectedAction(
+            LegacyTradingHaltWorkflowController.CurrentActionId);
+
+        Assert.Equal(searched.Results[0].SelectionId, searched.Selected?.SelectionId);
+        Assert.True(searched.Results[0].IsSelected);
+        Assert.All(searched.Actions, action => Assert.True(action.IsAvailable));
+        Assert.Equal("005930", current.StockCode);
+        Assert.Equal("가온전자", current.DisplayName);
+    }
+
     [Fact]
     public async Task SearchSelect_MaterializesClosedCurrentAndCandleDraftsFromActionIdOnly()
     {