feat(ui): Create content pattern components - DataTable, FilterBar, EmptyState, LoadingState

- Add LoadingState with table, card, list, and text skeleton patterns
- Add EmptyState with customizable icon, title, description, and action slot
- Add FilterBar with search input, clear button, and custom filter slot
- Add DataTable with TanStack Table integration, sorting, and row click
- Create barrel export index.ts for common components
- Install tanstack-table-8-svelte-5 for Svelte 5 compatibility
- Sync auth spec with authenticated user redirect requirements
- Archive p03-dashboard-enhancement

Refs: openspec/changes/p04-content-patterns
Closes: p04-content-patterns

frontend/package-lock.json

@@ -12,6 +12,7 @@
         "lucide-svelte": "^0.574.0",
         "recharts": "^2.15.1",
         "sveltekit-superforms": "^2.24.0",
+        "tanstack-table-8-svelte-5": "^0.1.2",
         "zod": "^3.24.2"
       },
       "devDependencies": {
@@ -5417,6 +5418,18 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/tanstack-table-8-svelte-5": {
+      "version": "0.1.2",
+      "resolved": "https://registry.npmjs.org/tanstack-table-8-svelte-5/-/tanstack-table-8-svelte-5-0.1.2.tgz",
+      "integrity": "sha512-wMRu7Y709GpRrbPSN6uiYPCsNk5J/ZjvNuHGCbSUNNZEs1u4q09qnoTbY1EcwGAb3RkDEHEyrE9ArJNT4w0HOg==",
+      "license": "MIT",
+      "dependencies": {
+        "@tanstack/table-core": "^8.20.5"
+      },
+      "peerDependencies": {
+        "svelte": "^5.0.0"
+      }
+    },
     "node_modules/tapable": {
       "version": "2.3.0",
       "resolved": "https://registry.npmjs.org/tapable/-/tapable-2.3.0.tgz",

frontend/package.json

@@ -49,6 +49,7 @@
     "lucide-svelte": "^0.574.0",
     "recharts": "^2.15.1",
     "sveltekit-superforms": "^2.24.0",
+    "tanstack-table-8-svelte-5": "^0.1.2",
     "zod": "^3.24.2"
   }
 }

frontend/src/lib/components/common/DataTable.svelte

@@ -0,0 +1,120 @@
+<script lang="ts" generics="T extends Record<string, any">
+	import { 
+		createSvelteTable,
+		getCoreRowModel,
+		getSortedRowModel,
+		type ColumnDef,
+		type SortingState,
+		type TableOptions
+	} from 'tanstack-table-8-svelte-5';
+	import { writable } from 'svelte/store';
+	import EmptyState from './EmptyState.svelte';
+	import LoadingState from './LoadingState.svelte';
+	import { ChevronUp, ChevronDown, ChevronsUpDown } from 'lucide-svelte';
+
+	interface Props {
+		data: T[];
+		columns: ColumnDef<T>[];
+		loading?: boolean;
+		emptyTitle?: string;
+		emptyDescription?: string;
+		onRowClick?: (row: T) => void;
+	}
+
+	let { 
+		data, 
+		columns, 
+		loading = false,
+		emptyTitle = 'No data',
+		emptyDescription = 'No records found.',
+		onRowClick
+	}: Props = $props();
+
+	const sorting = writable<SortingState>([]);
+	
+	const options: TableOptions<T> = {
+		data,
+		columns,
+		state: {
+			get sorting() {
+				return $sorting;
+			}
+		},
+		onSortingChange: (updater) => {
+			if (typeof updater === 'function') {
+				sorting.update(updater);
+			} else {
+				sorting.set(updater);
+			}
+		},
+		getCoreRowModel: getCoreRowModel(),
+		getSortedRowModel: getSortedRowModel()
+	};
+
+	const table = createSvelteTable(options);
+	
+	let rows = $derived($table.getRowModel().rows);
+	let isEmpty = $derived(!loading && rows.length === 0);
+	let headerGroups = $derived($table.getHeaderGroups());
+
+	function getSortIcon(columnId: string) {
+		const sort = $sorting.find(s => s.id === columnId);
+		if (!sort) return ChevronsUpDown;
+		return sort.desc ? ChevronDown : ChevronUp;
+	}
+
+	function getSortIconClass(columnId: string) {
+		const sort = $sorting.find(s => s.id === columnId);
+		return sort ? '' : 'opacity-50';
+	}
+</script>
+
+<div class="data-table overflow-x-auto">
+	{#if loading}
+		<LoadingState type="table" rows={5} columns={columns.length} />
+	{:else if isEmpty}
+		<EmptyState title={emptyTitle} description={emptyDescription} />
+	{:else}
+		<table class="table table-zebra table-pin-rows w-full">
+			<thead>
+				{#each headerGroups as headerGroup}
+					<tr>
+						{#each headerGroup.headers as header}
+							<th 
+								class={header.column.getCanSort() ? 'cursor-pointer select-none' : ''}
+								onclick={header.column.getToggleSortingHandler()}
+							>
+								<div class="flex items-center gap-2">
+									<span>{header.column.columnDef.header as string}</span>
+									{#if header.column.getCanSort()}
+										<span class={getSortIconClass(header.column.id)}>
+											<svelte:component this={getSortIcon(header.column.id)} size={14} />
+										</span>
+									{/if}
+								</div>
+							</th>
+						{/each}
+					</tr>
+				{/each}
+			</thead>
+			<tbody>
+				{#each rows as row}
+					<tr 
+						class={onRowClick ? 'cursor-pointer hover:bg-base-200' : ''}
+						onclick={() => onRowClick?.(row.original)}
+					>
+						{#each row.getVisibleCells() as cell}
+							<td>
+								{#if typeof cell.column.columnDef.cell === 'function'}
+									{cell.column.columnDef.cell(cell.getContext())}
+								{:else}
+									{cell.getValue()}
+								{/if}
+							</td>
+						{/each}
+					</tr>
+				{/each}
+			</tbody>
+		</table>
+	{/if}
+</div>

frontend/src/lib/components/common/EmptyState.svelte

@@ -0,0 +1,32 @@
+<script lang="ts">
+	import { Inbox } from 'lucide-svelte';
+	import type { Snippet } from 'svelte';
+	import type { ComponentType, SvelteComponent } from 'svelte';
+
+	interface Props {
+		title?: string;
+		description?: string;
+		icon?: ComponentType<SvelteComponent>;
+		children?: Snippet;
+	}
+
+	let { 
+		title = 'No data', 
+		description = 'No records found.',
+		icon: Icon = Inbox,
+		children 
+	}: Props = $props();
+</script>
+
+<div class="empty-state flex flex-col items-center justify-center py-12 text-center">
+	<div class="text-base-content/30 mb-4">
+		<svelte:component this={Icon} size={48} />
+	</div>
+	<h3 class="text-lg font-medium text-base-content/70">{title}</h3>
+	<p class="text-sm text-base-content/50 mt-1 max-w-sm">{description}</p>
+	{#if children}
+		<div class="mt-4">
+			{@render children()}
+		</div>
+	{/if}
+</div>

frontend/src/lib/components/common/FilterBar.svelte

@@ -0,0 +1,57 @@
+<script lang="ts">
+	import { Search, X } from 'lucide-svelte';
+	import type { Snippet } from 'svelte';
+
+	interface Props {
+		searchValue?: string;
+		searchPlaceholder?: string;
+		onSearchChange?: (value: string) => void;
+		onClear?: () => void;
+		children?: Snippet;
+	}
+
+	let { 
+		searchValue = '', 
+		searchPlaceholder = 'Search...',
+		onSearchChange,
+		onClear,
+		children 
+	}: Props = $props();
+
+	let hasFilters = $derived(searchValue !== '' || children !== undefined);
+</script>
+
+<div class="filter-bar flex flex-wrap items-center gap-3 mb-4">
+	<!-- Search Input -->
+	<div class="join">
+		<input 
+			type="text" 
+			class="input input-sm join-item w-64"
+			placeholder={searchPlaceholder}
+			value={searchValue}
+			oninput={(e) => onSearchChange?.(e.currentTarget.value)}
+		/>
+		<button class="btn btn-sm join-item" aria-label="Search">
+			<Search size={16} />
+		</button>
+	</div>
+
+	<!-- Custom Filters Slot -->
+	{#if children}
+		{@render children()}
+	{/if}
+
+	<!-- Clear Button -->
+	{#if hasFilters}
+		<button 
+			class="btn btn-ghost btn-sm gap-1"
+			onclick={() => {
+				onSearchChange?.('');
+				onClear?.();
+			}}
+		>
+			<X size={14} />
+			Clear
+		</button>
+	{/if}
+</div>

frontend/src/lib/components/common/LoadingState.svelte

@@ -0,0 +1,57 @@
+<script lang="ts">
+	interface Props {
+		type?: 'table' | 'card' | 'text' | 'list';
+		rows?: number;
+		columns?: number;
+	}
+
+	let { type = 'text', rows = 3, columns = 4 }: Props = $props();
+</script>
+
+<div class="loading-state" data-type={type}>
+	{#if type === 'table'}
+		<div class="space-y-2">
+			<!-- Header -->
+			<div class="flex gap-4">
+				{#each Array(columns) as _}
+					<div class="skeleton h-8 flex-1"></div>
+				{/each}
+			</div>
+			<!-- Rows -->
+			{#each Array(rows) as _}
+				<div class="flex gap-4">
+					{#each Array(columns) as _}
+						<div class="skeleton h-10 flex-1"></div>
+					{/each}
+				</div>
+			{/each}
+		</div>
+	{:else if type === 'card'}
+		<div class="card bg-base-100 shadow-sm">
+			<div class="card-body">
+				<div class="skeleton h-6 w-1/2 mb-2"></div>
+				<div class="skeleton h-4 w-full mb-1"></div>
+				<div class="skeleton h-4 w-3/4"></div>
+			</div>
+		</div>
+	{:else if type === 'list'}
+		<div class="space-y-3">
+			{#each Array(rows) as _}
+				<div class="flex items-center gap-3">
+					<div class="skeleton h-10 w-10 rounded-full"></div>
+					<div class="flex-1">
+						<div class="skeleton h-4 w-1/2 mb-1"></div>
+						<div class="skeleton h-3 w-1/4"></div>
+					</div>
+				</div>
+			{/each}
+		</div>
+	{:else}
+		<!-- text -->
+		<div class="space-y-2">
+			<div class="skeleton h-4 w-full"></div>
+			<div class="skeleton h-4 w-5/6"></div>
+			<div class="skeleton h-4 w-4/6"></div>
+		</div>
+	{/if}
+</div>

frontend/src/lib/components/common/index.ts

@@ -0,0 +1,6 @@
+// Content Pattern Components
+export { default as DataTable } from './DataTable.svelte';
+export { default as FilterBar } from './FilterBar.svelte';
+export { default as EmptyState } from './EmptyState.svelte';
+export { default as LoadingState } from './LoadingState.svelte';
+export { default as StatCard } from './StatCard.svelte';

frontend/tests/component/DataTable.spec.ts

@@ -0,0 +1,8 @@
+import { describe, it, expect } from 'vitest';
+import DataTable from '$lib/components/common/DataTable.svelte';
+
+describe('DataTable', () => {
+	it('exports a component module', () => {
+		expect(DataTable).toBeDefined();
+	});
+});

frontend/tests/component/EmptyState.spec.ts

@@ -0,0 +1,8 @@
+import { describe, it, expect } from 'vitest';
+import EmptyState from '$lib/components/common/EmptyState.svelte';
+
+describe('EmptyState', () => {
+	it('exports a component module', () => {
+		expect(EmptyState).toBeDefined();
+	});
+});

frontend/tests/component/FilterBar.spec.ts

@@ -0,0 +1,8 @@
+import { describe, it, expect } from 'vitest';
+import FilterBar from '$lib/components/common/FilterBar.svelte';
+
+describe('FilterBar', () => {
+	it('exports a component module', () => {
+		expect(FilterBar).toBeDefined();
+	});
+});

frontend/tests/component/LoadingState.spec.ts

@@ -0,0 +1,8 @@
+import { describe, it, expect } from 'vitest';
+import LoadingState from '$lib/components/common/LoadingState.svelte';
+
+describe('LoadingState', () => {
+	it('exports a component module', () => {
+		expect(LoadingState).toBeDefined();
+	});
+});