Phase 7: Search, filters, templates, and archive UI

Add full-text card search (PostgreSQL tsvector + GIN index) with navbar
SearchBar, client-side board filters (label/assignee/due date), board
templates (3 system templates + save-as-template API), and archive
toggle for both board listing and board view.

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

src/routes/+layout.svelte

@@ -4,6 +4,7 @@
 	import { onMount } from 'svelte';
 	import { connectSocket, disconnectSocket } from '$lib/stores/socket.js';
 	import NotificationBell from '$lib/components/NotificationBell.svelte';
+	import SearchBar from '$lib/components/SearchBar.svelte';
 
 	let { children, data }: { children: Snippet; data: { user: any; tenant: any } } = $props();
 
@@ -29,6 +30,10 @@
 					{data.tenant?.name ?? 'Pounce'}
 				</a>
 
+				{#if data.user}
+					<SearchBar />
+				{/if}
+
 				<div class="flex items-center gap-3">
 					{#if data.user}
 						{#if data.user.tenantRole === 'ADMIN' || data.user.globalRole === 'SITE_ADMIN'}