Replace file-based blog with API-backed service

BlogService now fetches from Media.JoshHeaps.Net API via HttpClient
with in-memory caching (5-min TTL) and stale cache fallback.
Removed Markdig/YamlDotNet dependencies. All page models now async.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

JoshHeaps.Net/wwwroot/js/utils.js

@@ -45,9 +45,9 @@ function simulateTyping(element, text, speed = 50) {
 
 function showClickedContents(option) {
     if (option === 'projects') {
-        document.querySelector("#ChessProject > div.diagonal-section-left").scrollIntoView({
+        document.querySelector("#ProjectsBox").scrollIntoView({
             behavior: "smooth",
-            block: "center",
+            block: "start",
             inline: "nearest"
         });
     }
@@ -68,4 +68,11 @@ function showClickedContents(option) {
             inline: "nearest"
         });
     }
+    else if (option === 'blog') {
+        document.querySelector("#BlogBox").scrollIntoView({
+            behavior: "smooth",
+            block: "start",
+            inline: "nearest"
+        });
+    }
 }