Enhance: Added toggle to apply styling in Lightbox conditionally

[Mayank-Tripathi32]

Attempt to resolve #67535, PR is aimed to explore the possibility.

What?

This PR introduces a toggle for the lightbox feature to conditionally apply styles.

Why?

Styles should only be applied within the site blocks and not inside the Lightbox. Since the Lightbox opens in a modal, there should be an option to disable custom site styles for it.

How?

• The lightbox attribute is updated to include a new applyStyles property, which defaults to true.
• If the lightbox feature is enabled, a new toggle option is added to BlockControls.
• This gives users the flexibility to disable custom styles specifically for Lightbox images.

Testing Instructions

• Add an image block to a Gutenberg-enabled page.
• Set the image block to the "Rounded" style within the "Styles" tab of the block settings sidebar.
• Use the link drop down of the contextual menu and select "Expand on click" on the image block.

Screenshots or screencast

demo.mp4

[github-actions]

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Co-authored-by: Mayank-Tripathi32 <mayanktripathi32@git.wordpress.org>
Co-authored-by: relic-se <ogrecooper@git.wordpress.org>

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[relic-se]

In order to maintain existing functionality on existing block-enabled content, the default value should be true if applyStyles is not already available within the lightbox block settings.
Correct me if I'm wrong here in case the default value defined in block.json is used in this situation.

[Mayank-Tripathi32]

Oh yes, I initially wrote the logic in reverse and then refactored it. I'll update it (though it won't make much of a difference since it defaults to true in block.json). It's fine to leave it as is. This is mainly for visual indication, and since the lightbox can be undefined when inactive, setting it to true might cause issues.