Improve file operations, layout memory, and drive status.

Add a sequential file-operations queue with pause, reorder, and optional auto-clear; persist window size and tree width; show free space; and clear leftover indexing status.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/Explorer.Application/LocationVisibility.cs

@@ -0,0 +1,46 @@
+using Explorer.Domain;
+
+namespace Explorer.Application;
+
+public static class LocationVisibility
+{
+    public static bool ShouldShow(LocationInfo info, UiPreferences preferences)
+    {
+        if (info.IsProtected)
+        {
+            return preferences.ShowProtectedSystemLocations;
+        }
+
+        if (info.IsHidden)
+        {
+            return preferences.ShowHiddenFiles;
+        }
+
+        return true;
+    }
+
+    public static SizeKnowledge ResolveSizeKnowledge(LocationInfo info, bool isDirectory, long sizeBytes, bool sizeFromIndex)
+    {
+        if (info.AccessDenied && sizeBytes <= 0)
+        {
+            return SizeKnowledge.Unknown;
+        }
+
+        if (info.AccessDenied && sizeBytes > 0)
+        {
+            return SizeKnowledge.Partial;
+        }
+
+        if (info.IsProtected && isDirectory && sizeBytes <= 0)
+        {
+            return SizeKnowledge.Unknown;
+        }
+
+        if (isDirectory && !sizeFromIndex && sizeBytes <= 0)
+        {
+            return SizeKnowledge.Unknown;
+        }
+
+        return SizeKnowledge.Calculated;
+    }
+}