- Extract handle_command() from interactive.rs to new commands.rs module
(320 lines, 15 match arms for /help, /compact, /thinnify, etc.)
- Fix orphaned tests in completion.rs that were outside mod tests block
- Add #[allow(dead_code)] to with_include_prompt_filename() (used in tests)
- interactive.rs reduced from 595 to 290 lines
Agent: fowler