pub async fn ensure_root_exists(root: &Path) -> Result<(), DaemonError>Expand description
Best-effort helper: ensure a root directory exists before serving.
Kept as a free function (not folded into RealLocalCacheStore::new)
so construction stays infallible and synchronous; callers await
this once at daemon startup.
§Errors
Propagates any I/O failure creating the directory.