807353cbe4
RepositoryImportSource::copyToFolder() called putContent() on the generic return type of Node::get(), which doesn't declare that method -- only File does. Existing-file overwrite during a per-user restore would have fatally errored at runtime; added an instanceof check and a resource leak fix (finally-close) while there. Also guarded getFileAsStream() against fopen() returning false. Everything else Psalm (strict level) currently flags is mechanical (missing `final` on leaf classes -- applied everywhere safe) or pre-existing array-shape/type gaps, captured in psalm-baseline.xml so CI fails only on new issues from here on, not the whole backlog at once.