Video: Fix blank first frame on iOS

[Infinite-Null]

Closes: #51995

What?

Fixes blank first frame issue in video blocks on iOS Safari by adding video.load() call in Script Module.

Why?

iOS Safari has a rendering timing issue where video elements show a blank/black frame before displaying the actual first frame of the video.

How?

• Adds a new Script Module (video/view.js) that targets iOS devices specifically
• Calls video.load() method to force the browser to reload and properly render the first frame
• Implements safeguards to prevent multiple executions on the same video element

Testing Instructions

1. Open iOS Simulator or use an actual iOS device
2. Create a new post or page in WordPress
3. Insert a Video block
4. Upload or select a video file
5. Publish/preview the page
6. Navigate to the published page on iOS Safari
7. Observe that the video displays the first frame immediately without showing a blank/black frame

Screencast

Before

https://github.com/user-attachments/assets/1575c810-ac3d-46b0-8577-fddeb0a390df

After

https://github.com/user-attachments/assets/c28fdce3-aa07-4a1e-b6b8-e93866f78443

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Co-authored-by: Infinite-Null <[email protected]>
Co-authored-by: fluiddot <[email protected]>

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