fix: make scratchpad scrollable (#3076)

## 📝 Summary

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Fixes #3073 . Each individual part can be scrolled (code editor, output
area, console output) and the whole scratchpad can be scrolled too. I
think it maintains the feel of scratchpad while handling long inputs /
outputs.

I'm not sure if it breaks anything else, so plan to test it locally a
while.

<img width="300" alt="Screenshot 2024-12-06 at 7 26 57 PM"
src="https://github.com/user-attachments/assets/0c777a17-8eca-4070-8ce2-bb5d7bf181ef">

## 🔍 Description of Changes

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## 📜 Reviewers

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@akshayka OR @mscolnick

frontend/src/components/scratchpad/scratchpad.tsx

@@ -269,7 +269,7 @@ export const ScratchPad: React.FC = () => {
           </Button>
         </Tooltip>
       </div>
-      <div className="flex-1 divide-y relative">
+      <div className="flex-1 divide-y relative overflow-hidden flex flex-col">
         {renderBody()}
         {renderHistory()}
       </div>