Prefer fakelib2 over fakelib for game overlays

Check app0/fakelib2 before resolving the legacy per-game fakelib
source. Fall back to app0/fakelib when fakelib2 is missing or is
not a directory.

README.md

@@ -124,7 +124,7 @@ Backport overlay behavior:
 - The `backports` folder is ignored during normal game scanning.
 - A backport is applied automatically to the matching mounted game from any configured scan path.
 - If multiple scan paths provide the same title backport, the game's own scan path wins; otherwise scan path order is used.
-- If `/mnt/sandbox/<TITLE_ID>_XXX/app0/fakelib` exists while the game is running, ShadowMount+ mounts it into that game's sandbox `common/lib`.
+- If `/mnt/sandbox/<TITLE_ID>_XXX/app0/fakelib2` exists while the game is running, ShadowMount+ mounts it into that game's sandbox `common/lib`; otherwise it falls back to `app0/fakelib`.
 - If `global_fakelib=1` and `global_fakelib_path` exists as a directory, ShadowMount+ also mounts that folder into the same sandbox `common/lib`.
 - When both global and per-game fakelib exist, the default gives the game's own `fakelib` priority by mounting `/data/shadowmount/fakelib` first and then the game-specific fakelib.
 - `global_fakelib_priority=global` reverses that priority.

config.ini.example

@@ -67,7 +67,7 @@
 # ufs_backend=lvd
 
 # Sandbox fakelib backport watcher:
-# 1/true/yes/on  -> mount /mnt/sandbox/<TITLE_ID>_XXX/app0/fakelib into common/lib
+# 1/true/yes/on  -> mount app0/fakelib2 when present, otherwise app0/fakelib, into common/lib
 # 0/false/no/off -> disable fakelib watcher
 # Default: 1
 # backport_fakelib=1

src/sm_fakelib.c

@@ -125,11 +125,17 @@ static bool resolve_sandbox_context(const char *title_id,
     return false;
 
   char source_path[MAX_PATH];
-  snprintf(source_path, sizeof(source_path), "/mnt/sandbox/%s/app0/fakelib",
+  snprintf(source_path, sizeof(source_path), "/mnt/sandbox/%s/app0/fakelib2",
            sandbox_id);
   struct stat st;
-  if (stat(source_path, &st) == 0 && S_ISDIR(st.st_mode))
+  if (stat(source_path, &st) == 0 && S_ISDIR(st.st_mode)) {
     (void)strlcpy(game_source_path, source_path, MAX_PATH);
+  } else {
+    snprintf(source_path, sizeof(source_path), "/mnt/sandbox/%s/app0/fakelib",
+             sandbox_id);
+    if (stat(source_path, &st) == 0 && S_ISDIR(st.st_mode))
+      (void)strlcpy(game_source_path, source_path, MAX_PATH);
+  }
 
   char sandbox_root[MAX_PATH];
   snprintf(sandbox_root, sizeof(sandbox_root), "/mnt/sandbox/%s", sandbox_id);