docs: Add installation instructions for .wnd patch files

Author: wahidkurdo

Patch/README.md

@@ -0,0 +1,30 @@
+# Custom Hotkey Remapping - Installation
+
+This patch adds in-game hotkey remapping for unit/building production keys per faction (USA, China, GLA).
+
+## Installation
+
+After building the game from source, copy the `.wnd` files to your Zero Hour installation:
+
+```
+Patch/Window/Menus/KeyboardOptionsMenu.wnd  →  <ZH Install>/Window/Menus/KeyboardOptionsMenu.wnd
+Patch/Window/Menus/OptionsMenu.wnd          →  <ZH Install>/Window/Menus/OptionsMenu.wnd
+```
+
+Replace `<ZH Install>` with your Zero Hour directory, for example:
+```
+C:\Program Files (x86)\EA Games\Command and Conquer Generals Zero Hour\
+```
+
+The loose `.wnd` files will override the ones inside `WindowZH.big` automatically.
+
+## What it does
+
+- Adds a **Keyboard Options** button to the Options menu
+- Opens a new menu with:
+  - **Category dropdown** (Control, Information, Interface, ... + Unit Keys: USA/China/GLA/Other)
+  - **Command list** showing all hotkeys for the selected category
+  - **Description and current key** display
+  - **Text input** to type a new key
+  - **Assign** and **Reset All** buttons
+- Hotkey overrides are saved per CommandButton name and persist across sessions