Improve the layout of Web Socket case study

[Jager-yoo]

Hi, I improved the layout of Web Socket case study.
Let me know what you think. Thank you! 😄

• The layout of the Web Socket was different from that of other cases. I modified it to have the same tone and manner.
• Also, there are multiple blue text buttons clustered together, making it a bit confusing. I modified it so that the roles of buttons are clearly distinguished.
• Messages are now stacking upward. And when re-connecting, the stacked messages are removed.
• I changed some text.

Please check out gif examples below. (1.5x speed)

as-is	to-be

[mbrandonw]

This looks much better, thanks for taking the time!