openai/gpt-chat-latest → A (5:1)

Side A makes a substantial architectural improvement by introducing a RocksDB-backed `durable` crate, moving raw Reddit entity payloads out of the in-memory tree into an `EntityStore`, and replacing event-log startup loading with streaming replay via `EventLog::replay`, reducing memory use and changing persistence design across the project. Side B is a valuable security fix—adding `ammonia` sanitization before rendering `selftext_html` and testing that scripts/event handlers are stripped—but it is a localized rendering hardening compared with A's broad, lasting infrastructure changes.