fix null error

/home/kushal/src/dotnet/MyBlog/src/MyBlog.Web/Components/Pages/PostDetail.razor(130,32): error CS8604: Possible null reference argument for parameter 'value' in 'void Dictionary<string, object>.Add(string key, object value)'.

Author: 9034725985

docs/llm/dump.txt

@@ -1,6 +1,6 @@
 ===============================================================================
 PROJECT EXPORT
-Generated: Wed Jan 21 12:48:41 PM EST 2026
+Generated: Fri Jan 23 09:35:11 AM EST 2026
 Project Path: /home/kushal/src/dotnet/MyBlog
 ===============================================================================
 
@@ -7793,7 +7793,7 @@ a:hover {
 
 
 ===============================================================================
-EXPORT COMPLETED: Wed Jan 21 12:48:42 PM EST 2026
+EXPORT COMPLETED: Fri Jan 23 09:35:12 AM EST 2026
 Total Files Found: 74
 Files Exported: 74
 Files Skipped: 0 (binary or large files)

src/MyBlog.Web/Components/Pages/PostDetail.razor

@@ -113,23 +113,23 @@ else
     {
         if (_post is null) return "";
 
-        var schema = new Dictionary<string, object>
+        var schema = new Dictionary<string, object?>
         {
             { "@context", "https://schema.org" },
             { "@type", "BlogPosting" },
             { "headline", _post.Title },
             { "description", _post.Summary },
-            { "author", new Dictionary<string, object> {
+            { "author", new Dictionary<string, object?> {
                 { "@type", "Person" },
                 { "name", _post.AuthorDisplayName }
             }},
-            { "publisher", new Dictionary<string, object> {
+            { "publisher", new Dictionary<string, object?> {
                 { "@type", "Organization" },
                 { "name", Configuration["Application:Title"] ?? "MyBlog" }
             }},
             { "datePublished", _post.PublishedAtUtc?.ToString("O") },
             { "dateModified", _post.UpdatedAtUtc.ToString("O") },
-            { "mainEntityOfPage", new Dictionary<string, object> {
+            { "mainEntityOfPage", new Dictionary<string, object?> {
                 { "@type", "WebPage" },
                 { "@id", _currentUrl }
             }}