chore(demo): rename DEMO (CN) to DEMO (OFFICIAL)

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: sunweiyue

minicpm-o-4_5/index.html

@@ -475,7 +475,7 @@
         <div class="hero-inner">
             <h1>MiniCPM-o 4.5 Audio Demo Page</h1>
             <div class="hero-links">
-                <a href="https://minicpm-omni.openbmb.cn/" target="_blank">DEMO (CN)</a>
+                <a href="https://minicpm-omni.openbmb.cn/" target="_blank">DEMO (OFFICIAL)</a>
                 <span class="sep">|</span>
                 <a href="https://huggingface.co/spaces/openbmb/MiniCPM-o-4_5-Demo" target="_blank">DEMO (HF)</a>
                 <span class="sep">|</span>