Add project files.

PrivacyGlass/HotkeyFilter.cs

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+
+using System;
+using System.Windows.Forms;
+
+namespace PrivacyGlass
+{
+    public class HotkeyFilter : IMessageFilter
+    {
+        private readonly Action onHotkey;
+        public HotkeyFilter(Action a) => onHotkey = a;
+
+        public bool PreFilterMessage(ref Message m)
+        {
+            if (m.Msg == 0x0312) // WM_HOTKEY
+            {
+                onHotkey();
+                return true;
+            }
+            return false;
+        }
+    }
+
+}