Fix auto-linking order and add dash-dash underline styling

- Moved auto-linking before markdown link processing to avoid conflicts
- Added dash-dash (dashed) underline for auto-links instead of dotted
- Improved pattern matching to avoid linking inside existing markdown links
- Enhanced detection of existing HTML tags and links
- Auto-links now have 2px dashed underline with hover effect

templates/layout.html

@@ -165,13 +165,15 @@
         .auto-link {
             color: #0d6efd;
             text-decoration: none;
-            border-bottom: 1px dotted #0d6efd;
+            border-bottom: 2px dashed #0d6efd;
             font-weight: 500;
+            transition: all 0.2s ease;
         }
         .auto-link:hover {
             color: #0a58ca;
             text-decoration: none;
             border-bottom-style: solid;
+            border-bottom-color: #0a58ca;
         }
         .search-form {
             max-width: 300px;