openai/gpt-chat-latest → A (20:1)

Commit A makes a substantial behavioral and storage-layer change. It replaces the recent-votes deque with an append-only list, updates the storage schema version, removes write-time trimming in favor of query-time capping, adjusts the in-memory representation, updates persistence logic and comments, removes obsolete code, and adds a regression test covering the new behavior. This affects data structures, persistence semantics, migration/versioning, and tests. Commit B is a small cleanup that simplifies an HTML form by removing client-side check attributes, with a minimal code change and much narrower impact.