get_recent_prompts returns {"prompts": [...]} but _get_fallback_prompt
indexed it like a list, so the last-resort link to the most recent prompt
always failed silently. Accept both shapes.
get_recent_prompts returns {"prompts": [...]} but _get_fallback_prompt
indexed it like a list, so the last-resort link to the most recent prompt
always failed silently. Accept both shapes.