feat: Fase 2a — shopping lists CRUD

DB: shopping_lists + shopping_items tables with full RLS, pg_cron jobs
(archive completed lists after 7 days, purge trash after 7 days).
item_frequency table with SECURITY DEFINER trigger that normalises and
upserts on every shopping_items INSERT.

Frontend: /lists overview (featured card + 2-col grid + trash toggle),
/lists/[id] detail (qty stepper, inline edit, swipe-to-reveal-delete,
drag & drop reorder via svelte-dnd-action, ItemSuggestions chips).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/web/src/lib/components/ItemSuggestions.svelte

@@ -0,0 +1,28 @@
+<script lang="ts">
+	import type { ItemFrequency } from '@colectivo/types';
+
+	interface Props {
+		suggestions: ItemFrequency[];
+		activePrefix: string;
+		onselect: (name: string) => void;
+	}
+
+	let { suggestions, activePrefix, onselect }: Props = $props();
+</script>
+
+{#if suggestions.length > 0}
+	<div class="flex flex-wrap gap-1.5 px-4 pb-2 pt-1">
+		{#each suggestions as item (item.name)}
+			<button
+				type="button"
+				onclick={() => onselect(item.name)}
+				class="rounded-full px-3 py-1 text-[13px] font-medium transition-colors
+					{activePrefix && item.name.startsWith(activePrefix.toLowerCase().trim())
+					? 'bg-slate-900 text-white dark:bg-white dark:text-slate-900'
+					: 'bg-slate-100 text-slate-700 hover:bg-slate-200 dark:bg-slate-800 dark:text-slate-300 dark:hover:bg-slate-700'}"
+			>
+				{item.name}
+			</button>
+		{/each}
+	</div>
+{/if}