Add Lunr.js for client-side search functionality and implement search results display

- Integrated Lunr.js library for indexing and searching content.
- Created search.js to handle search queries and display results dynamically.
- Implemented displayResults function to format and show search results.
- Enhanced search functionality with boosted fields for title and content.
- Added search.min.js for optimized production use.

config/_default/hugo.yaml

@@ -32,10 +32,16 @@ related:
     - name: date
       weight: 10
 
+outputFormats:
+  SearchIndex:
+    baseName: search
+    mediaType: application/json
+
 outputs:
   home:
     - html
     - rss
+    - SearchIndex
 
 services:
   rss: