d8e299dbb2
Somehow, the line of code responsible for freeing flushed nodes in `trie_writer` is missing from the implementation. This effectively means that `trie_writer` keeps the whole index in memory until the index writer is closed, which for many dataset is a guaranteed OOM. Fix that, and add some test that catches this. Fixes scylladb/scylladb#27082 Closes scylladb/scylladb#27083