[fix] Specify svg namespace if {@html} is used in svg

[baseballyama]

fix: #7450, #7002

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[dimfeld]

Nice! I believe this fixes #5764 as well.

[baseballyama]

Oh, I didn't know #5764.
And unfortunately, now this PR doesn't handle it.

I just quick look this, but for handling, I think we need to check parent element is SVG or not at mount function in runtime.
I think this would require a hack of the life cycle. If this is correct, I think we should defer to handling this until we know this is a major use case.

[baseballyama]

@tanhauhau

Thank you for your review!
Regarding lint, I created a new PR.
#7466

dont see much benefit for differentiating claim_svg_tag and claim_html_tag, can just do

I updated!