68e9d54fa5
Activity signals (tool calls like compress, grep, bash) were treated as 'progress' by the stagnation detector, resetting the stagnation counter every cycle. This prevented MAX_STAGNATION_COUNT from being reached, causing infinite continuation loops when models degrade to minimal responses in long sessions (e.g. GLM-5.1 at ~100K tokens). Stagnation now only tracks actual todo state changes: incomplete count decrease, completed count increase, or todo snapshot change. Tool-level activity no longer resets the stagnation counter.