add news for 2025-02-28

Announce the code freeze and in track for the IOCCC28 to open
on **2025-03-05 23:19:17.131107 UTC**.

sitemap.xml

@@ -15458,11 +15458,11 @@
 </url>
 <url>
     <loc>https://www.ioccc.org/news.html</loc>
-    <lastmod>2025-02-13T00:39:25+00:00</lastmod>
+    <lastmod>2025-03-01T02:11:48+00:00</lastmod>
 </url>
 <url>
     <loc>https://www.ioccc.org/news.md</loc>
-    <lastmod>2025-02-13T00:39:06+00:00</lastmod>
+    <lastmod>2025-03-01T02:11:45+00:00</lastmod>
 </url>
 <url>
     <loc>https://www.ioccc.org/README.html</loc>
@@ -15478,7 +15478,7 @@
 </url>
 <url>
     <loc>https://www.ioccc.org/status.json</loc>
-    <lastmod>2025-02-13T00:39:30+00:00</lastmod>
+    <lastmod>2025-03-01T02:15:13+00:00</lastmod>
 </url>
 <url>
     <loc>https://www.ioccc.org/thanks-for-help.html</loc>