Add UWP LocalState baserom discovery

README.md

@@ -255,6 +255,40 @@ build and install from source on a Mac instead, see
     <a href="https://github.com/bryanthaboi/gen1recomp/releases/latest"><img src="./.github/resources/github-badge.png" alt="Download from GitHub" height="60"></a>
 </div>
 
+## Xbox Dev Mode
+
+Every release ships `gen1recomp-*-xbox-uwp.zip` for Xbox One and Xbox Series
+consoles in Developer Mode. It cannot be installed in retail mode.
+
+Extract the archive, then use Xbox Device Portal to install the `.msix` and
+the x64 package under `Dependencies`.
+
+### External setup
+
+1. Put your legally obtained Red, Blue, or Yellow ROMs on an external drive.
+   Mod ZIPs can go on the same drive.
+2. Connect the drive to the Xbox and open Gen1Recomp.
+3. Select **Import ROM** or **Import Mod**, then choose the file with the Xbox
+   file picker.
+4. Repeat the ROM import for each version you want to use.
+
+### Internal setup
+
+1. Create a folder named `baseroms` on your PC and place your legally obtained
+   Red, Blue, or Yellow ROMs inside it.
+2. ZIP the folder, keeping `baseroms` at the top level of the archive.
+3. Launch Gen1Recomp once, then close it.
+4. Open Xbox Device Portal and upload the ZIP to
+   `Gen1Recomp/LocalState/pokemon-love2d/`.
+5. Choose **Yes** when Device Portal asks whether to extract the archive.
+6. Open Gen1Recomp. The launcher checks baseroms once at startup. When it finds a compatible ROM, that game’s tab shows ROM FOUND and an Import detected ROM button.
+
+ROMs, generated game data, saves, and mods remain in LocalState and are not
+included in the app.
+
+Source builds and package details are covered in
+[the Xbox UWP build notes](ports/uwp/BUILD.md).
+
 ## Handhelds
 
 A PortMaster-style port for the **Anbernic RG34XXSP** on Stock OS 64-bit MOD