Use playable README video preview

[terrywangcode]

Summary

• replace the README HTML video tag with an animated GIF preview that renders directly on GitHub
• keep the MP4 link for the full intro video with audio
• sync the same treatment in README.zh-CN.md

Testing

• preview asset generated from docs/assets/openhive-product-intro.mp4
• documentation/media-only change

[gemini-code-assist]

Code Review

This pull request replaces the embedded video in the README files with a GIF preview linked to the full video. Feedback suggests merging the image and text links into a single anchor tag to improve accessibility and recommends using a looping video tag instead of a GIF for better performance and visual quality.

[gemini-code-assist]

The image link and the text link both point to the same destination. Combining them into a single link improves accessibility for screen reader users by reducing redundancy and creates a cleaner layout by grouping the preview with its description. Additionally, consider using a

Suggested change

	<p align="center">
	<video src="docs/assets/openhive-product-intro.mp4" controls playsinline width="100%" title="OpenHive product introduction"></video>
	<a href="docs/assets/openhive-product-intro.mp4">
	<img src="docs/assets/openhive-product-intro.gif" alt="OpenHive product introduction video preview" width="100%" />
	</a>
	</p>
	<p align="center">
	<a href="docs/assets/openhive-product-intro.mp4">Watch the OpenHive product intro video</a>
	<a href="docs/assets/openhive-product-intro.mp4">Watch the OpenHive product intro video with audio</a>
	</p>
	<p align="center">
	<a href="docs/assets/openhive-product-intro.mp4">
	<img src="docs/assets/openhive-product-intro.gif" alt="OpenHive product introduction video preview" width="100%" />
	<br />
	Watch the OpenHive product intro video with audio
	</a>
	</p>

[gemini-code-assist]

The image link and the text link both point to the same destination. Combining them into a single link improves accessibility for screen reader users by reducing redundancy and creates a cleaner layout by grouping the preview with its description. Additionally, consider using a

Suggested change

	<p align="center">
	<video src="docs/assets/openhive-product-intro.mp4" controls playsinline width="100%" title="OpenHive 产品介绍"></video>
	<a href="docs/assets/openhive-product-intro.mp4">
	<img src="docs/assets/openhive-product-intro.gif" alt="OpenHive 产品介绍视频预览" width="100%" />
	</a>
	</p>
	<p align="center">
	<a href="docs/assets/openhive-product-intro.mp4">观看 OpenHive 产品介绍视频</a>
	<a href="docs/assets/openhive-product-intro.mp4">观看带声音的 OpenHive 产品介绍视频</a>
	</p>
	<p align="center">
	<a href="docs/assets/openhive-product-intro.mp4">
	<img src="docs/assets/openhive-product-intro.gif" alt="OpenHive 产品介绍视频预览" width="100%" />
	<br />
	观看带声音的 OpenHive 产品介绍视频
	</a>
	</p>