Project: svelte
Task (challenging): 1) Add appealing Comments.svelte with the title 'Comments' at the bottom of Blog.svelte. 2) Include a TextArea with the placeholder 'Enter Your Comment' and a submit button (.comment-btn) to submit the comment. 3) Only display comments related to the selected blog, showing them in cards with the className '.comment-item', placed above the TextArea. 4) Create stores/commentStore.ts to implement CommentStore using Svelte's store mechanism, and connect CommentStore to UI. 5) Preserve comments when a blog is edited, and clear them when a blog is deleted. 6) Constraint: DO NOT USE any third-party packages; ONLY utilize Svelte APIs.