feat(shared): add MetaLine primitive — · -separated meta, optional icon (§7)

Refs #859
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/lib/shared/primitives/MetaLine.svelte

@@ -0,0 +1,26 @@
+<script lang="ts">
+let {
+	items,
+	iconSrc
+}: {
+	items: string[];
+	iconSrc?: string;
+} = $props();
+</script>
+
+{#if items.length > 0}
+	<div
+		data-testid="meta-line"
+		style="display:flex; align-items:center; flex-wrap:wrap; gap:8px; font-family:var(--font-sans); font-size:12px; color:var(--c-ink-2);"
+	>
+		{#if iconSrc}
+			<img src={iconSrc} alt="" style="width:14px; height:14px; opacity:0.5; flex-shrink:0;" />
+		{/if}
+		{#each items as item, i (i)}
+			{#if i > 0}
+				<span data-testid="meta-sep" aria-hidden="true">·</span>
+			{/if}
+			<span data-testid="meta-item">{item}</span>
+		{/each}
+	</div>
+{/if}

frontend/src/lib/shared/primitives/MetaLine.svelte.spec.ts

@@ -0,0 +1,74 @@
+import { afterEach, describe, expect, it } from 'vitest';
+import { cleanup, render } from 'vitest-browser-svelte';
+import MetaLine from './MetaLine.svelte';
+
+afterEach(() => cleanup());
+
+describe('MetaLine', () => {
+	it('renders N item spans when given N items', async () => {
+		render(MetaLine, { items: ['14. März 1923', '14 Dokumente', '4 Personen'] });
+		const spans = document.querySelectorAll('[data-testid="meta-item"]');
+		expect(spans).toHaveLength(3);
+		expect(spans[0].textContent).toBe('14. März 1923');
+		expect(spans[1].textContent).toBe('14 Dokumente');
+		expect(spans[2].textContent).toBe('4 Personen');
+	});
+
+	it('renders separator spans between items', async () => {
+		render(MetaLine, { items: ['A', 'B', 'C'] });
+		const seps = document.querySelectorAll('[data-testid="meta-sep"]');
+		// N items → N-1 separators
+		expect(seps).toHaveLength(2);
+		expect(seps[0].textContent).toBe('·');
+	});
+
+	it('renders nothing when items is empty', async () => {
+		const { container } = render(MetaLine, { items: [] });
+		// No element children — Svelte may leave an empty comment node but no DOM elements
+		expect(container.querySelectorAll('[data-testid]')).toHaveLength(0);
+		expect(container.querySelectorAll('div, span, img')).toHaveLength(0);
+	});
+
+	it('renders nothing when items has one element (no separator)', async () => {
+		render(MetaLine, { items: ['Nur eines'] });
+		const seps = document.querySelectorAll('[data-testid="meta-sep"]');
+		expect(seps).toHaveLength(0);
+		const spans = document.querySelectorAll('[data-testid="meta-item"]');
+		expect(spans).toHaveLength(1);
+	});
+
+	it('shows the leading img when iconSrc is supplied', async () => {
+		render(MetaLine, {
+			items: ['Datum'],
+			iconSrc: '/degruyter-icons/Simple/Small-16px/SVG/Action/Calendar-Add-SM.svg'
+		});
+		const img = document.querySelector('img');
+		expect(img).not.toBeNull();
+	});
+
+	it('does NOT render an img when iconSrc is omitted', async () => {
+		render(MetaLine, { items: ['Datum'] });
+		const img = document.querySelector('img');
+		expect(img).toBeNull();
+	});
+
+	it('icon has width 14px, height 14px, opacity 0.5, and alt=""', async () => {
+		render(MetaLine, {
+			items: ['Datum'],
+			iconSrc: '/degruyter-icons/Simple/Small-16px/SVG/Action/Calendar-Add-SM.svg'
+		});
+		const img = document.querySelector('img') as HTMLImageElement;
+		expect(img.alt).toBe('');
+		// Inline style values (set directly on the element, not via getComputedStyle)
+		expect(img.style.width).toBe('14px');
+		expect(img.style.height).toBe('14px');
+		expect(img.style.opacity).toBe('0.5');
+	});
+
+	it('applies font-size 12px to the wrapper', async () => {
+		render(MetaLine, { items: ['Test'] });
+		const wrapper = document.querySelector('[data-testid="meta-line"]') as HTMLElement;
+		expect(wrapper).not.toBeNull();
+		expect(wrapper.style.fontSize).toBe('12px');
+	});
+});