Phase 8 decision: Xbox 360 pad (ViGEm) stays preferred on Win10/11

vJoy is fallback-only on modern Windows and the primary backend on XP.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/PLAN.md

@@ -324,8 +324,9 @@ lamps, plasma, wallpaper apply).
 - **8B — vJoy sink (both flavors):** `VJoyJoystickSink : IJoystickSink`
   P/Invoking `vJoyInterface.dll` (SDK already on hand in docs/vJoy_SDK/);
   arch-matched DLL load; report packing pure + unit-tested. Acquisition
-  order — net48: ViGEm → RioGamepad → **vJoy** → Null (a signed 96-button
-  option on 10/11 for free); net40: vJoy → Null. Pin installers:
+  order (decided): **the Xbox 360 pad (ViGEm) stays preferred on 10/11** —
+  net48: ViGEm → RioGamepad → vJoy → Null (vJoy is fallback only);
+  net40: vJoy → Null (the XP primary). Pin installers:
   2.0.5 (XP) / 2.1.9.1 (signed, 10/11) in `deploy/vendor/`.
 - **8C — Tray on net40/x86:** multi-target `RioJoy.Tray` (net40 drops the
   ViGEm + RioJoy.Overlay references); gate `WallpaperMakerForm` + overlay
@@ -345,9 +346,11 @@ lamps, plasma, wallpaper apply).
   (joy.cpl shows 6 axes + 96 buttons, SendInput into a game, lamps,
   plasma, auto-switch yield, BMP wallpaper).
 - **To confirm before starting:** (1) keep the mapping editor on XP or ship
-  runtime-only? (2) is vJoy acceptable as the 10/11 full-fidelity fallback
-  (96 buttons without the custom driver)? (3) which XP cabinets / how do
-  files get onto them (drives the .bat installer shape)?
+  runtime-only? (2) which XP cabinets / how do files get onto them (drives
+  the .bat installer shape)?
+  *Decided:* the Xbox 360 pad (ViGEm) remains the preferred controller on
+  Windows 10/11 whenever ViGEmBus is present; vJoy is only the fallback
+  there, and the primary on XP.
 
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