use block events for llm stats

[LasmarKhalifa]

Current LLM stats output (after "Repeat log prefix on each line of multi-line output" is merged):

Proposed new LLM stats output:

[LasmarKhalifa]

• use block events for llm stats #902 👈 (View in Graphite)
• Use block events in Pi agent cogs #901
• Use block events in chat cogs #900
• Use block events in claude #899
• Add a block type event #898
• Repeat log prefix on each line of multi-line output #893
• main

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[juniper-shopify]

"Agent Stats" doesn't need to be in all caps here anymore, nor in square brackets. It was only like that because there wasn't a better way to make a "header" stand out before we had this new formatter. Maybe it's still better in all caps, but feel free to think about how you'd like to style the header line now that you've got cleaner block formatting

[LasmarKhalifa]

I like the all caps format, because it makes it stand out from the output and for consistency with the LLM response/prompt headers. But I agree that there could be a discussion on the way we want to format headers (for all of them, including response and prompt headers). I'll mark it up as ready but if you think there could be a cleaner formatting, let me know!!

Potential candidates:

(Current for reference)