Function generated_key_path 

pub fn generated_key_path(store_dir: &Path) -> PathBuf

Resolve the generated key-file path for a store directory.

Standard layouts pass <store-root>/lmdb to the store open: the key is placed at the store root, <store-root>/.at_rest_key, next to .seal_key — outside the directory that LMDB maintenance and restore tooling rewrites. Non-standard layouts (tests, custom paths whose final component is not lmdb) keep the key inside the directory passed in.