feat(docker-watcher): phase 14 - frontend polish & modern UI

Design system with CSS custom properties (light/dark themes).
38 Lucide SVG icon components. Dark mode with system preference.
EN/RU localization with i18n store. Skeleton loaders, empty states,
toggle switches, micro-interactions. Responsive sidebar with
mobile hamburger menu. All pages polished with consistent styling.

web/src/lib/components/SkeletonCard.svelte

@@ -0,0 +1,24 @@
+<!--
+  Task 8: Skeleton card placeholder for project cards during loading.
+-->
+<script lang="ts">
+	import Skeleton from './Skeleton.svelte';
+</script>
+
+<div class="rounded-xl border border-[var(--border-primary)] bg-[var(--surface-card)] p-5 shadow-[var(--shadow-sm)]">
+	<div class="flex items-start justify-between">
+		<div class="flex-1 space-y-2">
+			<Skeleton width="60%" height="1.25rem" />
+			<Skeleton width="80%" height="0.875rem" />
+		</div>
+		<Skeleton width="4rem" height="1.5rem" rounded />
+	</div>
+	<div class="mt-4 flex gap-4">
+		<Skeleton width="5rem" height="0.875rem" />
+		<Skeleton width="4rem" height="0.875rem" />
+	</div>
+	<div class="mt-3 flex gap-3">
+		<Skeleton width="3.5rem" height="0.75rem" />
+		<Skeleton width="4.5rem" height="0.75rem" />
+	</div>
+</div>