Added author name display to blog

[vidipsingh]

This PR addresses issue #571 by adding the author's name below the title of blog posts. The author’s name is fetched from the front matter and displayed in the blog layout as "by Author Name."

Changes Made:

• Added dynamic display for the author name in the blog post layout.
• The author field in the front matter is now rendered below the post title.
• Updated CSS classes for styling the author name and post date.

Issue Link:

Closes #571

How to Test:

1. Add author: "Author Name" to the front matter of any blog post.
2. Verify that the author's name is correctly displayed below the post title.

Additional Notes:

This implementation improves post attribution by clearly displaying the author's name for each blog post.

Screenshots:

Before:

After:

[pikurasa]

@vidipsingh I'm merging it.

In the future, please create a separate branch (not master) and create the PR from that branch.

Also, please include the number of any related issue in the commit message. For this, it would have been "Fixes #571" at the end of your message.

[vidipsingh]

@pikurasa Apologies for missing that. I’ll follow the process correctly next time.
Thanks for merging my PR!