feat: add config viewer page for /[username]/[slug]

Display snapshot details including formulae, casks, macOS prefs, shell config.
Hero section with one-liner install command.

Author: fullstackjam

src/routes/[username]/[slug]/+page.server.ts

@@ -0,0 +1,46 @@
+import { error } from '@sveltejs/kit';
+import type { PageServerLoad } from './$types';
+import { getCurrentUser } from '$lib/server/auth';
+
+export const load: PageServerLoad = async ({ params, platform, request, cookies }) => {
+	const { username, slug } = params;
+	const env = platform?.env;
+	if (!env) throw error(500, 'Platform env not available');
+
+	// 1. Find user
+	const targetUser = await env.DB.prepare('SELECT id, username FROM users WHERE username = ?')
+		.bind(username)
+		.first<{ id: string; username: string }>();
+
+	if (!targetUser) throw error(404, 'User not found');
+
+	// 2. Find config
+	const config = await env.DB.prepare(
+		'SELECT * FROM configs WHERE user_id = ? AND slug = ?'
+	)
+		.bind(targetUser.id, slug)
+		.first<any>();
+
+	if (!config) throw error(404, 'Configuration not found');
+
+	// 3. Check visibility
+	if (!config.is_public) {
+		const currentUser = await getCurrentUser(request, cookies, env.DB, env.JWT_SECRET);
+		if (!currentUser || currentUser.id !== targetUser.id) {
+			throw error(404, 'Configuration not found'); // Hide private configs
+		}
+	}
+
+	// Parse JSON fields
+	try {
+		config.snapshot = JSON.parse(config.snapshot);
+		config.packages = JSON.parse(config.packages);
+	} catch (e) {
+		console.error('Failed to parse config JSON', e);
+	}
+
+	return {
+		configUser: targetUser,
+		config
+	};
+};