Resolve backend inventory from checkout

tools/inventory/platform-interface-inventory.py

@@ -54,7 +54,7 @@ def main() -> int:
     args = parser.parse_args()
 
     catalog = json.loads((META_ROOT / "repositories.json").read_text(encoding="utf-8"))
-    workspace_root = Path(catalog["default_parent"]).resolve()
+    workspace_root = _resolve_workspace_root(catalog)
     webui = _extract_webui()
     backend_endpoints = _extract_backend_endpoints(catalog, workspace_root)
     manifests = _extract_manifests(catalog, workspace_root)
@@ -103,6 +103,27 @@ def main() -> int:
     return 0
 
 
+def _resolve_workspace_root(catalog: dict[str, Any]) -> Path:
+    sibling_root = META_ROOT.parent.resolve()
+    configured_root = Path(str(catalog["default_parent"])).expanduser().resolve()
+    repositories = catalog.get("repositories")
+    if not isinstance(repositories, list):
+        raise ValueError("repository catalog has no repositories array")
+
+    def source_count(root: Path) -> int:
+        return sum(
+            1
+            for item in repositories
+            if isinstance(item, dict)
+            and isinstance(item.get("path"), str)
+            and (root / item["path"] / "src").is_dir()
+        )
+
+    sibling_count = source_count(sibling_root)
+    configured_count = source_count(configured_root)
+    return sibling_root if sibling_count >= configured_count else configured_root
+
+
 def _extract_webui() -> dict[str, Any]:
     helper = META_ROOT / "tools" / "inventory" / "extract-webui-structure.mjs"
     completed = subprocess.run(