SiPE paper blog link

[hriaz17]

Adds a link to the blog post accompanying our EMNLP 2026 paper, Introducing Syntax-Informed Positional Embeddings (SiPE).

Since the site has no blog section yet, this adds a blog.md page in the same style as press.md. It uses the shared default layout and appears in the nav automatically through the order front matter, so no changes to the layout or config are needed.

I am not sure this is how you would like blog posts handled, so please treat the page itself as a proposal rather than a fixed choice. See my comment below.

Related: #52 adds the paper to the publications bib.

[hriaz17]

Hi Mihai @MihaiSurdeanu, before this gets merged I wanted to check how you would like blog posts integrated into the site, since there is no blog section yet.

A few options, roughly in increasing order of effort:

1. A simple list page, which is what this PR does: one blog.md in the same style as press.md, linking out to posts hosted elsewhere. Nothing else changes, and it appears in the nav automatically via the order front matter.
2. Fold it into the existing pages instead of adding a new one, for example a Blog section at the bottom of press.md, or just the url_Blog link on the publications entry (already in add EMNLP 2026 paper #52). That avoids adding a nav item at all.
3. Proper Jekyll posts under _posts/, with a post layout and an index page, so posts are hosted on clulab.org rather than linked out. More setup, but better if we expect a steady stream of posts from the lab.

I went with option 1 as the least invasive, but I am happy to redo it either of the other ways, or to drop the nav entry if you would rather it not appear there. Also let me know if you would prefer a different date format or ordering convention for future entries.

Thanks!

[MihaiSurdeanu]

Let's add a "blog" link under the respective paper. I think that's easiest to find as I suspect this is where people who care about the paper will look.