fix: reconcile package and CLI template drift (batch 1)

[Shewart]

Part of #52. Eight components where one copy was plainly wrong or behind the other.

Package:

• Label: For was accepted but never rendered as for.
• FileUpload: the icon needed the Material Symbols font, which the package does not ship. Now an inline SVG, as in the CLI template.
• Sheet: the close button was missing when only Description was set.
• Sheet, Drawer, SheetContent, DrawerContent: clicks inside the panel reached parent click handlers.

CLI templates:

• CarouselItem: divide by zero when TotalSlides is 0.
• SidebarMenuButton: collapsed-icon styling from the package.
• Menubar: border follows the theme colour.
• ThemeToggle: class building matches the package.

Also adds a markup comparison to TemplateSyncTests for these components (the existing test only compares @code blocks), regenerates the class safelist, and corrects the roadmap: the Select, ContextMenu, NavigationMenu and Carousel parts already have CLI templates.

180 of 217 package components now match their templates. Build has 0 warnings, 349 tests pass. Not checked in a browser.

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