fix: address PR review feedback round 3

Build warnings (CA1304):
- ThemedImages: pass CultureInfo.CurrentUICulture to ResourceManager.GetObject

API consistency:
- PaintHelper.BookmarkMarkerTextColor property -> GetBookmarkMarkerTextColor(bool darkMode) method, matching other PaintHelper APIs

Minor cleanup:
- LogWindow.ApplyResourceImages: cache Application.IsDarkModeEnabled into local variable
- LogTabWindow.ApplyThemedImages: early return in light mode to avoid unnecessary bitmap reloads

PR description updates (per reviewer request):
- Default dark-mode grid text changes from Color.White to Color.FromArgb(220, 220, 220) (soft gainsboro tone)
- Removed assets (no code references remain): 13 light/dark icon pairs, LogExpert.bmp, LogExpert-Icon.gif, Icon1.ico, Icon2.ico, bubble.ico
- Installer and ApplicationIcon already use logexpert.ico, cleanup is safe

Pro_Filter note:
- Pro_Filter uses neutral line art that is readable on both light and dark backgrounds, so no Pro_Filter_dark variant is needed.

Author: mfkeeq199458

src/LogExpert.Resources/ThemedImages.cs

@@ -1,20 +1,23 @@
 using System.Drawing;
+using System.Globalization;
 
 namespace LogExpert;
 
 public static class ThemedImages
 {
     public static Bitmap Get (string name, bool darkMode)
     {
+        var culture = CultureInfo.CurrentUICulture;
+
         if (darkMode)
         {
-            if (Resources.ResourceManager.GetObject(name + "_dark") is Bitmap dark)
+            if (Resources.ResourceManager.GetObject(name + "_dark", culture) is Bitmap dark)
             {
                 return dark;
             }
         }
 
-        return (Bitmap)(Resources.ResourceManager.GetObject(name)
+        return (Bitmap)(Resources.ResourceManager.GetObject(name, culture)
             ?? throw new InvalidOperationException($"Themed image resource '{name}' (or '{name}_dark') was not found."));
     }
 }

src/LogExpert.UI/Controls/LogWindow/LogWindow.cs

@@ -531,10 +531,11 @@ private void SetResources ()
 
     private void ApplyResourceImages ()
     {
+        var darkImages = Application.IsDarkModeEnabled;
         pnlProFilterLabel.BackgroundImage = Resources.Pro_Filter;
-        btnFilterDown.BackgroundImage = ThemedImages.Get("ArrowDown", Application.IsDarkModeEnabled);
-        btnFilterUp.BackgroundImage = ThemedImages.Get("ArrowUp", Application.IsDarkModeEnabled);
-        btnToggleHighlightPanel.Image = ThemedImages.Get("Arrow_menu_open", Application.IsDarkModeEnabled);
+        btnFilterDown.BackgroundImage = ThemedImages.Get("ArrowDown", darkImages);
+        btnFilterUp.BackgroundImage = ThemedImages.Get("ArrowUp", darkImages);
+        btnToggleHighlightPanel.Image = ThemedImages.Get("Arrow_menu_open", darkImages);
     }
 
     private void ApplyCheckBoxResources ()
@@ -6644,7 +6645,7 @@ public void CellPainting (bool focused, int rowIndex, int columnIndex, bool isFi
                         var fontName = isFilteredGridView ? FONT_VERDANA : FONT_COURIER_NEW;
                         var stringToDraw = isFilteredGridView ? "!" : "i";
 
-                        using var brush2 = new SolidBrush(PaintHelper.BookmarkMarkerTextColor);
+                        using var brush2 = new SolidBrush(PaintHelper.GetBookmarkMarkerTextColor(Application.IsDarkModeEnabled));
                         using var font = new Font(fontName, Preferences.Font.Size, FontStyle.Bold);
                         e.Graphics.DrawString(stringToDraw, font, brush2, new RectangleF(rect.Left, rect.Top, rect.Width, rect.Height), _format);
                     }

src/LogExpert.UI/Dialogs/LogTabWindow/LogTabWindow.cs

@@ -390,6 +390,11 @@ private void ApplyThemedImages ()
     {
         var dark = Application.IsDarkModeEnabled;
 
+        if (!dark)
+        {
+            return;
+        }
+
         openToolStripMenuItem.Image = ThemedImages.Get("File_open", dark);
         closeFileToolStripMenuItem.Image = ThemedImages.Get("Close", dark);
         reloadToolStripMenuItem.Image = ThemedImages.Get("Restart_alt", dark);

src/LogExpert.UI/Entities/PaintHelper.cs

@@ -75,7 +75,7 @@ public static void CellPainting (ILogPaintContextUI logPaintCtx, bool focused, i
 
                     if (bookmark.Text.Length > 0)
                     {
-                        using var brush2 = new SolidBrush(BookmarkMarkerTextColor);
+                        using var brush2 = new SolidBrush(GetBookmarkMarkerTextColor(Application.IsDarkModeEnabled));
                         using var font = logPaintCtx.MonospacedFont;
                         e.Graphics.DrawString("i", font, brush2, new RectangleF(r.Left, r.Top, r.Width, r.Height), _format);
                     }
@@ -107,10 +107,12 @@ public static Color GetForeColorFromHighlightEntry (HighlightEntry? entry, bool
         return darkMode ? _darkModeForeColor : Color.Black;
     }
 
-    public static Color BookmarkMarkerTextColor =>
-        Application.IsDarkModeEnabled
+    public static Color GetBookmarkMarkerTextColor (bool darkMode)
+    {
+        return darkMode
             ? Color.FromArgb(255, 90, 45, 0)     // dark brown-orange, readable on the light bookmark fills used in dark mode
             : Color.FromArgb(255, 190, 100, 0); // DarkOrange baseline
+    }
 
     [SupportedOSPlatform("windows")]
     public static Brush GetBrushForFocusedControl (bool focused, Color selectionColor, bool darkMode)