docs: add demo and FAQ sections, update mkdocs configuration for improved navigation

docs/en/demo.md

+<script
+	type="module"
+	src="https://gradio.s3-us-west-2.amazonaws.com/5.35.0/gradio.js"
+></script>
+
+<gradio-app src="https://opendatalab-mineru.hf.space"></gradio-app>

docs/zh/demo.md

+<iframe title="iframe" allowfullscreen="" class="iframeResizer___U3wJg" src="https://opendatalab-mineru.ms.show?t=1752577214918&amp;__theme=dark&amp;studio_token=1d5b1c59-136a-4bee-9812-20113cb91762&amp;backend_url=/" allow="accelerometer; ambient-light-sensor; autoplay; battery; camera; clipboard-read; clipboard-write; display-capture; document-domain; encrypted-media; fullscreen; geolocation; gyroscope; layout-animations; legacy-image-formats; magnetometer; microphone; midi; oversized-images; payment; picture-in-picture; publickey-credentials-get; sync-xhr; usb; vr ; wake-lock; xr-spatial-tracking" id="iFrameResizer0" style="min-height: calc(-40px + 100vh); width: 100%; flex-grow: 1; border: medium; overflow: auto; height: 1746px;"></iframe>
\ No newline at end of file

mkdocs.yml

@@ -58,9 +58,13 @@ nav:
       - CLI Tools: usage/cli_tools.md
       - Model Source: usage/model_source.md
       - Advanced CLI Parameters: usage/advanced_cli_parameters.md
+    - Output File Format: output_files.md
+    - FAQ: faq.md
+    - Demo: demo.md
   - Output File Format: output_files.md
-  - FAQ:
-      - FAQ: FAQ/index.md
+  - FAQ: faq.md
+  - Demo: demo.md
+
 
 plugins:
   - search
@@ -83,7 +87,7 @@ plugins:
             CLI Tools: 命令行工具
             Model Source: 模型源
             Advanced CLI Parameters: 命令行参数进阶技巧
-            FAQ: FAQ
+            FAQ: 常见问题解答
             Output File Format: 输出文件格式
   - mkdocs-video