New Duo Code Review workflow is too slow compared to legacy flow

Problem

Extracted from &18645 (comment 2775888761)

Duo Code Review workflow in Duo Agent Platform takes too long when compared with the legacy workflow.

From @kinsingh:

reviews are very slow in the production environment. I am still trying to investigate the root cause behind this, but my hunch is that we trigger the workflow from the monolith side and that probably generates a job that just sits in the queue for quite a bit.

I was able to enable extended logging for my username in the production environment and can see that the actual LLM review part via the flow execution only took about ~232 seconds (overall review took 17 minutes), which is an acceptable timeframe in my opinion. The majority of the time was spent fetching the MR data (take a look at the screenshot below).

Screenshot