Page Summary feature is not utilizing the entire side bar area, instead adding an unnecessary scroll bar

Steps to reproduce the issue:

1. Create a fresh Orion profile
2. Sign in to Kagi
3. Open an article, e.g. https://trace.yshui.dev/2024-08-copy-core-dumps.html
4. Use the context menu to summarize it
5. Notice that the summary does not occupy the entire side window, and a scroll bar is instead added:
   
6. The Key Moments type also partially suffers from this issue but sometimes it correctly occupies the entire available area.

Video of the issue:

Expected functionality:
The summary feature should correctly use the available space and only introduce scroll bars when it is necessary to do so.

Version 0.99.128.2-rc (WebKit 619.1.11.111.2)

Sonoma (14)