feat(mvp): phase 4 - app registry & healthcheck

Add app CRUD API endpoints, healthcheck service with node-cron scheduler,
icon resolver (Lucide, Simple Icons, CDN, uploads), app management UI
with Superforms, health badge component, and Docker health endpoint.

src/lib/components/app/AppHealthBadge.svelte

@@ -0,0 +1,25 @@
+<script lang="ts">
+	interface Props {
+		status: string;
+	}
+
+	let { status }: Props = $props();
+
+	const config = $derived.by(() => {
+		switch (status) {
+			case 'online':
+				return { color: 'bg-green-500', text: 'Online' };
+			case 'offline':
+				return { color: 'bg-red-500', text: 'Offline' };
+			case 'degraded':
+				return { color: 'bg-yellow-500', text: 'Degraded' };
+			default:
+				return { color: 'bg-gray-500', text: 'Unknown' };
+		}
+	});
+</script>
+
+<span class="inline-flex items-center gap-1.5 text-xs">
+	<span class="inline-block h-2 w-2 rounded-full {config.color}"></span>
+	<span class="text-muted-foreground">{config.text}</span>
+</span>