feat(phase2): phase 6 - integration & polish

Fix all build/type/lint errors, write 60 new tests (175 total),
update seed with new widget types and team board permissions,
install missing svelte-i18n dependency, fix DynamicIcon for Svelte 5.

src/lib/components/widget/NoteWidget.svelte

@@ -37,6 +37,7 @@
 
 <div class="flex h-full flex-col rounded-xl border border-border bg-card p-4">
 	<div class="prose prose-sm prose-invert max-w-none flex-1 overflow-auto text-foreground">
+		<!-- eslint-disable-next-line svelte/no-at-html-tags -- content is sanitized above -->
 		{@html renderedContent}
 	</div>
 </div>