Add BSIPA bootstrap support

src/plugin_helper/config.py

@@ -4,12 +4,21 @@ import os
 from pathlib import Path
 
 
-DEFAULT_INSTANCES_ROOT = Path("/home/pleb/Windows/Users/pleb/BSManager/BSInstances")
+WINDOWS_INSTANCES_ROOT = Path("/home/pleb/Windows/Users/pleb/BSManager/BSInstances")
+LOCAL_INSTANCES_ROOT = Path.home() / ".local/share/BSManager/BSInstances"
+DEFAULT_INSTANCES_ROOTS = (WINDOWS_INSTANCES_ROOT, LOCAL_INSTANCES_ROOT)
+DEFAULT_INSTANCES_ROOT = WINDOWS_INSTANCES_ROOT
 
 
 def instances_root(value: str | None = None) -> Path:
+    return instances_roots(value)[0]
+
+
+def instances_roots(value: str | None = None) -> list[Path]:
     raw = value or os.environ.get("PLUGIN_HELPER_INSTANCES_ROOT")
-    return Path(raw).expanduser() if raw else DEFAULT_INSTANCES_ROOT
+    if raw:
+        return [Path(item).expanduser() for item in raw.split(os.pathsep) if item]
+    return list(DEFAULT_INSTANCES_ROOTS)
 
 
 def state_root(value: str | None = None) -> Path: