Task token-usage totals now skip advisor and compaction iterations when picking the latest usable one
The function that computes a sub-agent task's token usage, used for cost and usage display, now skips iterations of type advisor_message or compaction when looking for the most recent usable iteration to report on. If no valid message iteration is found, it falls back to the running totals instead. Numeric validation on each token field is also stricter than before.
This avoids showing token counts drawn from an advisor message or a compaction step (where the model condenses conversation history) as if they were a normal turn's usage, keeping the reported token numbers more accurate.