Accessibility add alt to images

[Arhell]

• Please check if the PR fulfills these requirements

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resolve #435

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[fisherxu]

Could you please add some descriptions for this PR? Thanks

[Arhell]

Could you please add some descriptions for this PR? Thanks

Of course.
Because assistive technologies can’t interpret an image directly, they rely on alternative text to communicate the image's meaning to users. If an image has (non-empty) alternative text, the image is identified as meaningful, and its alternative text is presented to the user.

[fisherxu]

/approve
cc @anvithks Plz help take a look :)

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[Arhell]

Please take a look, it's been a while since you merged with the main branch.