Scroll regression: can't scroll conversation history at all

Bug

Since a recent update, it's impossible to scroll through conversation history.

What broke:

• Scroll wheel now captured by input box (multiline input change)
• Ctrl+O transcript viewer only shows current page, not full history
• Shift+scroll doesn't work
• No way to read back through a long session

Expected: Mouse scroll scrolls conversation history like before

Impact: Major UX regression — product is unusable for long sessions. History is completely inaccessible.