Plan is for full CoT summaries to be visible in a "transcript view" when we implement that, but for now they're hidden. https://github.com/user-attachments/assets/e8a1b0ef-8f2a-48ff-9625-9c3c67d92cdb
Replace mixed `⎿` and `L` prefixes with `└` in TUI rendering. <img width="454" height="659" alt="Screenshot 2025-08-13 at 4 02 03 PM" src="https://github.com/user-attachments/assets/61c9c7da-830b-4040-bb79-a91be90870ca" />
Wait for newlines, then render markdown on a line by line basis. Word wrap it for the current terminal size and then spit it out line by line into the UI. Also adds tests and fixes some UI regressions.