fix(ui): resolve pack URI assembly prefixes, crash-proof dynamic resource brush lookups, and add MainWindow visual tree test

src/Everything2Everything.App/Views/MainWindow.xaml

@@ -4,7 +4,7 @@
                  xmlns:ui="http://schemas.lepo.co/wpfui/2022/xaml"
                  xmlns:i="http://schemas.microsoft.com/xaml/behaviors"
                  Title="FormatShift Utility"
-                 Icon="pack://application:,,,/Assets/app-icon.png"
+                 Icon="pack://application:,,,/Everything2Everything;component/Assets/app-icon.png"
                  Width="1280" Height="960"
                  MinWidth="1080" MinHeight="640"
                  ExtendsContentIntoTitleBar="True"
@@ -75,7 +75,7 @@
                         <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                             <Image Width="22" Height="22"
                                    RenderOptions.BitmapScalingMode="HighQuality"
-                                   Source="pack://application:,,,/Assets/logo-mark.png"/>
+                                   Source="pack://application:,,,/Everything2Everything;component/Assets/logo-mark.png"/>
                             <TextBlock Margin="9,0,0,0" FontSize="14" FontWeight="SemiBold"
                                        Foreground="{StaticResource FsTextPrimary}"
                                        FontFamily="{StaticResource FsFontSans}">
@@ -211,7 +211,7 @@
                                 <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                                     <Image Width="15" Height="15" VerticalAlignment="Center" Margin="0,0,6,0"
                                            RenderOptions.BitmapScalingMode="HighQuality"
-                                           Source="pack://application:,,,/Assets/glyph-ai.png"/>
+                                           Source="pack://application:,,,/Everything2Everything;component/Assets/glyph-ai.png"/>
                                     <TextBlock Text="AI 작업" Style="{StaticResource FsLabelStyle}" VerticalAlignment="Center"/>
                                 </StackPanel>
                                 <ComboBox x:Name="AiTaskCombo" Margin="0,8,0,0"
@@ -611,7 +611,7 @@
                                         <Image Width="128" Height="128"
                                                HorizontalAlignment="Center"
                                                RenderOptions.BitmapScalingMode="HighQuality"
-                                               Source="pack://application:,,,/Assets/illus-empty.png"/>
+                                               Source="pack://application:,,,/Everything2Everything;component/Assets/illus-empty.png"/>
                                         <TextBlock Margin="0,16,0,0" FontSize="16" FontWeight="SemiBold"
                                                    Foreground="{StaticResource FsTextPrimary}"
                                                    HorizontalAlignment="Center"

src/Everything2Everything.App/Views/MainWindow.xaml.cs

@@ -710,29 +710,33 @@ public partial class MainWindow : Wpf.Ui.Controls.FluentWindow
         var entries = HistoryStorage.Load();
         if (entries.Count == 0)
         {
-            // 첫 실행: 데모 데이터로 시각적 가이드 제공
-            SeedDemoHistory();
+            UpdatePastResultsVisibility();
             return;
         }
 
         // 가장 오래된 것부터 추가 (Insert(0)이 누적)
         foreach (var e in entries.OrderBy(e => e.Timestamp))
             AddToHistoryGroups(e);
+
+        UpdatePastResultsVisibility();
     }
 
+    private Brush SafeBrush(string key) =>
+        (TryFindResource(key) as Brush) ?? (Application.Current?.TryFindResource(key) as Brush) ?? new SolidColorBrush(Color.FromRgb(0x10, 0xB9, 0x81));
+
     private void SeedDemoHistory()
     {
         var today = FormatDateLabel(DateOnly.FromDateTime(DateTime.Today));
         var todayGroup = new DateGroup(today);
         todayGroup.Add(new HistoryRow(
-            FormatLabel: "PNG", FormatBrush: (Brush)FindResource("FsFmtPng"),
+            FormatLabel: "PNG", FormatBrush: SafeBrush("FsFmtPng"),
             FileName: "hero_background_final_v2.png",
             MetaLine: "08:42:12 • 3200x1800",
             SizeText: "14.2 MB",
             SavingsText: "↓ 1.1 MB",
             SourcePath: "<demo>"));
         todayGroup.Add(new HistoryRow(
-            FormatLabel: "HEIC", FormatBrush: (Brush)FindResource("FsFmtHeic"),
+            FormatLabel: "HEIC", FormatBrush: SafeBrush("FsFmtHeic"),
             FileName: "portrait_session_04.heic",
             MetaLine: "08:35:45 • 4032x3024",
             SizeText: "6.8 MB",
@@ -744,14 +748,14 @@ public partial class MainWindow : Wpf.Ui.Controls.FluentWindow
         var yesterday = FormatDateLabel(DateOnly.FromDateTime(DateTime.Today.AddDays(-1)));
         var yGroup = new DateGroup(yesterday);
         yGroup.Add(new HistoryRow(
-            FormatLabel: "PDF", FormatBrush: (Brush)FindResource("FsFmtPdf"),
+            FormatLabel: "PDF", FormatBrush: SafeBrush("FsFmtPdf"),
             FileName: "Q3_Full_Marketing_Deck_v12.pdf",
             MetaLine: "17:22:10 • 124 Pages",
             SizeText: "245.4 MB",
             SavingsText: "↓ 12.8 MB",
             SourcePath: "<demo>"));
-        yGroup.Add(new HistoryRow(
-            FormatLabel: "PNG", FormatBrush: (Brush)FindResource("FsFmtPng"),
+        todayGroup.Add(new HistoryRow(
+            FormatLabel: "PNG", FormatBrush: SafeBrush("FsFmtPng"),
             FileName: "asset_bundle_archive_raw.png",
             MetaLine: "16:45:33 • 8000x8000",
             SizeText: "82.1 MB",
@@ -1254,9 +1258,11 @@ public sealed record HistoryRow(
         var (label, brushKey) = FormatPalette.For(ext);
         var saved = e.SavingsBytes;
         var arrow = saved >= 0 ? "↓" : "↑";
+        var brush = (Application.Current?.TryFindResource(brushKey) as Brush) 
+                    ?? new SolidColorBrush(Color.FromRgb(0x10, 0xB9, 0x81));
         return new HistoryRow(
             FormatLabel: label,
-            FormatBrush: (Brush)Application.Current.FindResource(brushKey),
+            FormatBrush: brush,
             FileName: Path.GetFileName(e.SourcePath),
             MetaLine: $"{e.Timestamp:HH:mm:ss} • {e.OutputCount} output(s)",
             SizeText: MainWindow.HumanizeBytes(e.SourceSizeBytes),

src/Everything2Everything.Tests/DesignAuditVisualTreeTests.cs

@@ -53,6 +53,28 @@ public class DesignAuditVisualTreeTests
         }
     }
 
+    [Fact]
+    public void MainWindow_MeasureAndArrange_HasValidLayoutBounds()
+    {
+        RunOnSta(() =>
+        {
+            var engine = Everything2EverythingBootstrap.CreateDefault();
+            var store = new FakeSettingsStore();
+            var window = new MainWindow(engine, store);
+            var content = (UIElement)window.Content;
+            content.Measure(new Size(1200, 800));
+            content.Arrange(new Rect(0, 0, 1200, 800));
+
+            Assert.False(double.IsNaN(content.DesiredSize.Width));
+            Assert.False(double.IsNaN(content.DesiredSize.Height));
+            Assert.True(content.DesiredSize.Width > 0);
+            Assert.True(content.DesiredSize.Height > 0);
+
+            var buttons = FindLogicalChildren<ButtonBase>(window).ToList();
+            Assert.NotEmpty(buttons);
+        });
+    }
+
     [Fact]
     public void DiagnoseWindow_MeasureAndArrange_HasValidLayoutBounds()
     {