Launcher: no exception for Proton, it has a folder of its own there too

- The launcher refuses to start from a Steam library folder under
  Wine/Proton as well; the check is no longer skipped there.
- README, Linux (Proton): the launcher and ReSkate.dll go in a new, empty
  folder, and the Steam launch option swaps in the launcher's full path in
  place of EA's anti-cheat launcher. Noted as not yet tested on Proton; the
  earlier test was with the launcher beside Skate.exe.

Launcher/main.cpp

@@ -91,11 +91,9 @@ void run_headless(const app::Session& session, std::vector<std::wstring> argumen
 
 // Whether the launcher was put in a game's folder of a Steam library (...\steamapps\common\<game>),
 // which is where Steam keeps skate. and updates it: ReSkate has a folder of its own, with its
-// own copy of the game. Not under Wine: on Proton, Steam starts the launcher from the game's
-// folder in the game's place, and that is how it is set up there (README, "Linux (Proton)").
+// own copy of the game. The same under Wine: on Proton, Steam is given the launcher's place in
+// that folder of its own (README, "Linux (Proton)").
 bool in_steam_library() {
-    const auto ntdll = GetModuleHandleW(L"ntdll.dll");
-    if (ntdll && GetProcAddress(ntdll, "wine_get_version")) return false;
     std::wstring self(32768, L' ');
     self.resize(GetModuleFileNameW(nullptr, self.data(), static_cast<DWORD>(self.size())));
     if (self.empty()) return false;

README.md

@@ -57,16 +57,17 @@ ReSkate supports one game build at a time (Steam build `25414733`).
 
 ### Linux (Proton)
 
-1. Install skate. with Steam and put `ReSkateLauncher.exe` and `ReSkate.dll` beside `Skate.exe`, in
-   Steam's skate. folder (Steam → skate. → Manage → Browse local files). Proton is the one case where
-   the launcher goes there, because Steam has to start it in the game's place.
-2. In Steam → skate. → Properties → Launch Options, enter:
+1. Install skate. with Steam, and put `ReSkateLauncher.exe` and `ReSkate.dll` in a new, empty folder
+   of their own, for example `~/Games/ReSkate` (not Steam's skate. folder: the launcher refuses to
+   run from there).
+2. In Steam → skate. → Properties → Launch Options, enter this with your own folder's path:
 
    ```
-   bash -c 'exec "${@/EAAntiCheat.GameServiceLauncher.exe/ReSkateLauncher.exe}"' -- %command%
+   bash -c 'exec "${@/*EAAntiCheat.GameServiceLauncher.exe//home/you/Games/ReSkate/ReSkateLauncher.exe}"' -- %command%
    ```
 
-3. Press **Play** on skate. in your Steam library.
+3. Press **Play** on skate. in your Steam library. The launcher installs its own copy of the game
+   into that folder the first time.
 
 Steam starts EA's anti-cheat launcher (`EAAntiCheat.GameServiceLauncher.exe`), not `Skate.exe`, and the
 anti-cheat refuses to run under Proton (*E111000B … Wine, Proton, and Steam Deck are not supported*).
@@ -74,8 +75,9 @@ The launch option swaps it for ReSkate's launcher, which starts the game itself.
 own Steam entry, rather than adding the launcher as a non-Steam game, keeps skate.'s app ID and its
 Proton prefix.
 
-Tested with ReSkate 1.1.3 and Proton Experimental on CachyOS: the launcher, the server browser, joining
-a public server and hosting a lobby. Steam Deck should work the same way but is untested. If you load a
+The launcher in a folder of its own is new and has not been tested on Proton yet. With the launcher
+beside `Skate.exe`, as it was set up before, ReSkate 1.1.3 was tested with Proton Experimental on
+CachyOS: the launcher, the server browser, joining a public server and hosting a lobby. Steam Deck should work the same way but is untested. If you load a
 custom map and then join a server on another map, the screen can stay black
 ([#31](https://github.com/Dingo-Shenanigans/ReSkate/issues/31)): load the server's map first.