Drop Fomantic tab, checkbox and form patches (#37377)

Clean up the fomantic helpers that nothing inside fomantic depends on.
Manually tested all functionality.

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Co-authored-by: Claude (Opus 4.7) <noreply@anthropic.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

templates/repo/diff/image_diff.tmpl

@@ -7,8 +7,8 @@
 			data-mime-before="{{.sniffedTypeBase.GetMimeType}}"
 			data-mime-after="{{.sniffedTypeHead.GetMimeType}}"
 		>
-			<overflow-menu class="ui secondary pointing tabular menu custom">
-				<div class="overflow-menu-items tw-justify-center">
+			<overflow-menu class="ui secondary pointing tabular menu">
+				<div class="overflow-menu-items tw-justify-center" data-global-init="initTabSwitcher">
 					<a class="item active" data-tab="diff-side-by-side-{{.file.NameHash}}">{{ctx.Locale.Tr "repo.diff.image.side_by_side"}}</a>
 					{{if and .blobBase .blobHead}}
 					<a class="item" data-tab="diff-swipe-{{.file.NameHash}}">{{ctx.Locale.Tr "repo.diff.image.swipe"}}</a>