Function parse_codex_line 

pub fn parse_codex_line(line: &str) -> ParsedLine

Parse one line of codex exec --json JSONL into the shared ParsedLine. Assistant text is the full agent_message on item.completed; tool items (command_execution, file_change, web_search, mcp_tool_call) become structured tool cards (ToolStart/ToolEnd). Codex edits files directly via tools (reflected on disk by the file watcher), so it never emits suggested-edit previews — edits stays empty.