Manually inserting a codeblock adding three backticks and hitting enter
is not functioning in the ToastUI editor due to an existing bug in the library.
This commit implements a workaround to address the issue.
The editor will now have a default height of 300px but a button will let
the user expand the editor. It will expand it to fit all content (or up
to 400px if the content was not exceeding 300px). In the expanded mode
the editor will keep growing as the user types more content.
The default ToastUI image insertion feature includes both URL and file
upload options. However, file upload functionality isn't supported in
the application. This commit addresses the issue by implementing custom
code to hide the file upload button while preserving the URL insertion
option.
