fix: correct catalog error contrast and add catalog Storybook coverage

apps/web/.storybook/preview.js

@@ -1,4 +1,11 @@
+import { setup } from '@storybook/vue3';
+
 import '../src/assets/styles/global.scss';
+import { storybookRouter } from './router.js';
+
+setup((app) => {
+  app.use(storybookRouter);
+});
 
 export const globalTypes = {
   theme: {

apps/web/.storybook/router.js

@@ -0,0 +1,24 @@
+import { createMemoryHistory, createRouter } from 'vue-router';
+
+const stub = { render: () => null };
+
+// Mirrors the named routes in src/router/index.js so RouterLink resolution
+// works in isolated stories without importing the real app router/guards.
+export const storybookRouter = createRouter({
+  history: createMemoryHistory(),
+  routes: [
+    { path: '/', name: 'catalog', component: stub },
+    { path: '/listings/:id', name: 'listing-detail', component: stub },
+    { path: '/products/:slug', name: 'product-detail', component: stub },
+    { path: '/login', name: 'login', component: stub },
+    { path: '/admin', name: 'admin-home', component: stub },
+    { path: '/admin/inventory/:id/images', name: 'admin-image-manager', component: stub },
+    { path: '/admin/inventory', name: 'admin-inventory', component: stub },
+    { path: '/admin/listings', name: 'admin-listings', component: stub },
+    { path: '/admin/sales', name: 'admin-sales', component: stub },
+    { path: '/admin/acquisitions', name: 'admin-acquisitions', component: stub },
+    { path: '/admin/settings', name: 'admin-settings', component: stub },
+    { path: '/admin/saved-views', name: 'admin-saved-views', component: stub },
+    { path: '/:pathMatch(.*)*', name: 'storybook-catch-all', component: stub },
+  ],
+});

apps/web/.storybook/test-runner.js

@@ -0,0 +1,10 @@
+// Forces a narrow viewport for stories that specifically exercise mobile-only
+// CSS breakpoints, since @storybook/addon-viewport does not affect the
+// headless iframe size that @storybook/test-runner navigates to directly.
+export default {
+  async preVisit(page, context) {
+    if (context.id?.startsWith('pages-catalogpage--mobile')) {
+      await page.setViewportSize({ width: 375, height: 900 });
+    }
+  },
+};