Add academic metadata: citation_date

Author: matthewsmawfield

site/index.html

@@ -72,7 +72,7 @@
     <!-- Google Scholar Meta Tags -->
     <meta name="citation_title" content="Global Time Echoes: Raw RINEX Validation of Distance-Structured Correlations in GNSS Clocks">
     <meta name="citation_author" content="Smawfield, Matthew Lukin">
-    <meta name="citation_date" content="2025/12/15">
+    <meta name="citation_date" content="2025-12-24">
     <meta name="citation_author_institution" content="Independent Researcher">
     <meta name="citation_author_email" content="matthewsmawfield@gmail.com">
     <meta name="citation_author_orcid" content="https://orcid.org/0009-0003-8219-3159">