Auto mode can classify questions instead of stopping

In auto mode, deciding to ask on the AskUserQuestion tool no longer automatically counts as needing a human and halting the run; it can be classified and handled instead. CLAUDE_CODE_AUTO_MODE_CLASSIFY_ASK_USER_QUESTION decides this if set; otherwise the server-side auto mode config's classifyAskUserQuestion value applies and is treated as on unless it is explicitly false, so with no server value the new behaviour is active.