feat: improve UX when extension fails to create new comment

This MR introduces improved error handling when creating a new comment fails.

before	after
before-comment-error-handling	better-failed-comment-ux
User had to find their message in logs and copy-paste it to retry	User can just click Add Comment Now again.

This MR also changes Sentence case to Title case for all commands (!308 (comment 627709834))

Related to #398 (closed)