Cache: fix 1-year CSS cache and add version busting

- .htaccess: remove duplicate cache block that set all CSS/JS to max-age=31536000
  CSS/JS now use max-age=3600 must-revalidate (was 1 year, breaking live edits)
- index.php: bump main.min.css version v1.1.3 -> v1.1.4
- All 78 PHP files: add ?v=20260222 to main.css and cro-enhancements.css refs
  Forces browser cache bust for all pages after todays accessibility changes

404.php

@@ -17,7 +17,7 @@ $page_description = "The page you're looking for doesn't exist. Explore our data
     <link rel="preconnect" href="https://fonts.googleapis.com">
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
     <link href="https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap" rel="stylesheet">
-    <link rel="stylesheet" href="assets/css/main.css">
+    <link rel="stylesheet" href="assets/css/main.css?v=20260222">
     
     <style>
         .error-page {