feat(manacore/web): add tag drag-and-drop to workbench pages

- Mount DragPreview + draggable tag bar on workbench homepage
- Add dropTarget on list items in todo, calendar, contacts ListViews
- Show assigned tags as colored dots on list items
- Tags can be dragged from the tag bar onto any item to assign them
- Drop target highlights with module-colored outline on hover

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/manacore/apps/web/src/lib/modules/calendar/ListView.svelte

@@ -10,9 +10,21 @@
 	import { eventsStore } from './stores/events.svelte';
 	import { Plus } from '@manacore/shared-icons';
 	import type { ViewProps } from '$lib/components/workbench/nav-stack';
+	import { dropTarget } from '@manacore/shared-ui/dnd';
+	import type { TagDragData } from '@manacore/shared-ui/dnd';
+	import { getTagsByIds } from '$lib/stores/tags.svelte';
 
 	let { navigate, goBack, params }: ViewProps = $props();
 
+	function handleTagDrop(eventId: string, tagData: TagDragData) {
+		const event = events.find((e) => e.id === eventId);
+		if (!event) return;
+		const current = event.tagIds ?? [];
+		if (!current.includes(tagData.id)) {
+			eventsStore.updateTagIds(eventId, [...current, tagData.id]);
+		}
+	}
+
 	let events = $state<LocalEvent[]>([]);
 
 	const now = new Date();
@@ -121,6 +133,7 @@
 		</form>
 
 		{#each todayEvents as event (event.id)}
+			{@const eventTags = getTagsByIds(event.tagIds ?? [])}
 			<button
 				class="event-card"
 				onclick={() =>
@@ -129,8 +142,22 @@
 						_siblingIds: todayEvents.map((e) => e.id),
 						_siblingKey: 'eventId',
 					})}
+				use:dropTarget={{
+					accepts: ['tag'],
+					onDrop: (p) => handleTagDrop(event.id, p.data as unknown as TagDragData),
+					canDrop: (p) => !(event.tagIds ?? []).includes((p.data as unknown as TagDragData).id),
+				}}
 			>
-				<p class="event-title">{event.title}</p>
+				<div class="event-header">
+					<p class="event-title">{event.title}</p>
+					{#if eventTags.length > 0}
+						<div class="event-tags">
+							{#each eventTags as tag (tag.id)}
+								<span class="tag-dot" style="background: {tag.color}" title={tag.name}></span>
+							{/each}
+						</div>
+					{/if}
+				</div>
 				<p class="event-time-label">
 					{#if event.allDay}
 						Ganztägig
@@ -277,6 +304,28 @@
 	:global(.dark) .event-card:hover {
 		background: rgba(255, 255, 255, 0.06);
 	}
+	.event-header {
+		display: flex;
+		align-items: center;
+		justify-content: space-between;
+		gap: 0.375rem;
+	}
+	.event-tags {
+		display: flex;
+		gap: 0.25rem;
+		flex-shrink: 0;
+	}
+	.tag-dot {
+		width: 6px;
+		height: 6px;
+		border-radius: 9999px;
+		flex-shrink: 0;
+	}
+	:global(.event-card.mana-drop-target-hover) {
+		outline: 2px solid rgba(59, 130, 246, 0.4);
+		outline-offset: -2px;
+		background: rgba(59, 130, 246, 0.06) !important;
+	}
 	.event-title {
 		font-size: 0.8125rem;
 		font-weight: 500;

apps/manacore/apps/web/src/lib/modules/contacts/ListView.svelte

@@ -10,9 +10,21 @@
 	import { contactsStore } from './stores/contacts.svelte';
 	import { Plus, Star } from '@manacore/shared-icons';
 	import type { ViewProps } from '$lib/components/workbench/nav-stack';
+	import { dropTarget } from '@manacore/shared-ui/dnd';
+	import type { TagDragData } from '@manacore/shared-ui/dnd';
+	import { getTagsByIds } from '$lib/stores/tags.svelte';
 
 	let { navigate, goBack, params }: ViewProps = $props();
 
+	function handleTagDrop(contactId: string, tagData: TagDragData) {
+		const contact = contacts.find((c) => c.id === contactId);
+		if (!contact) return;
+		const current = contact.tagIds ?? [];
+		if (!current.includes(tagData.id)) {
+			contactsStore.updateTagIds(contactId, [...current, tagData.id]);
+		}
+	}
+
 	let contacts = $state<LocalContact[]>([]);
 	let search = $state('');
 
@@ -86,6 +98,7 @@
 
 	<div class="contact-list">
 		{#each filtered() as contact (contact.id)}
+			{@const contactTags = getTagsByIds(contact.tagIds ?? [])}
 			<button
 				class="contact-item"
 				onclick={() =>
@@ -94,6 +107,11 @@
 						_siblingIds: filtered().map((c) => c.id),
 						_siblingKey: 'contactId',
 					})}
+				use:dropTarget={{
+					accepts: ['tag'],
+					onDrop: (p) => handleTagDrop(contact.id, p.data as unknown as TagDragData),
+					canDrop: (p) => !(contact.tagIds ?? []).includes((p.data as unknown as TagDragData).id),
+				}}
 			>
 				<div class="avatar">{initials(contact)}</div>
 				<div class="contact-info">
@@ -101,6 +119,13 @@
 					{#if contact.company}
 						<p class="contact-company">{contact.company}</p>
 					{/if}
+					{#if contactTags.length > 0}
+						<div class="contact-tags">
+							{#each contactTags as tag (tag.id)}
+								<span class="tag-dot" style="background: {tag.color}" title={tag.name}></span>
+							{/each}
+						</div>
+					{/if}
 				</div>
 				{#if contact.isFavorite}
 					<span class="fav"><Star size={12} weight="fill" /></span>
@@ -251,6 +276,22 @@
 		text-overflow: ellipsis;
 		white-space: nowrap;
 	}
+	.contact-tags {
+		display: flex;
+		gap: 0.25rem;
+		margin-top: 0.125rem;
+	}
+	.tag-dot {
+		width: 6px;
+		height: 6px;
+		border-radius: 9999px;
+		flex-shrink: 0;
+	}
+	:global(.contact-item.mana-drop-target-hover) {
+		outline: 2px solid rgba(34, 197, 94, 0.4);
+		outline-offset: -2px;
+		background: rgba(34, 197, 94, 0.06) !important;
+	}
 	.fav {
 		color: #f59e0b;
 		display: flex;

apps/manacore/apps/web/src/lib/modules/todo/ListView.svelte

@@ -15,9 +15,25 @@
 	import { tasksStore } from './stores/tasks.svelte';
 	import { Circle, Check } from '@manacore/shared-icons';
 	import type { ViewProps } from '$lib/components/workbench/nav-stack';
+	import { dropTarget } from '@manacore/shared-ui/dnd';
+	import type { TagDragData } from '@manacore/shared-ui/dnd';
+	import { getTagsByIds } from '$lib/stores/tags.svelte';
 
 	let { navigate, goBack, params }: ViewProps = $props();
 
+	function getTaskTagIds(task: import('./types').Task): string[] {
+		return ((task.metadata as Record<string, unknown>)?.labelIds as string[]) ?? [];
+	}
+
+	function handleTagDrop(taskId: string, tagData: TagDragData) {
+		const task = tasks.find((t) => t.id === taskId);
+		if (!task) return;
+		const current = getTaskTagIds(task);
+		if (!current.includes(tagData.id)) {
+			tasksStore.updateLabels(taskId, [...current, tagData.id]);
+		}
+	}
+
 	type ViewFilter = 'inbox' | 'today' | 'overdue';
 
 	let filter = $state<ViewFilter>('inbox');
@@ -92,6 +108,8 @@
 
 	<div class="task-list">
 		{#each filtered() as task (task.id)}
+			{@const taskTagIds = getTaskTagIds(task)}
+			{@const taskTags = getTagsByIds(taskTagIds)}
 			<button
 				onclick={() =>
 					navigate('detail', {
@@ -100,6 +118,11 @@
 						_siblingKey: 'taskId',
 					})}
 				class="task-item"
+				use:dropTarget={{
+					accepts: ['tag'],
+					onDrop: (p) => handleTagDrop(task.id, p.data as unknown as TagDragData),
+					canDrop: (p) => !taskTagIds.includes((p.data as unknown as TagDragData).id),
+				}}
 			>
 				<div
 					class="checkbox"
@@ -114,8 +137,15 @@
 				</div>
 				<div class="task-content">
 					<p class="task-title" class:completed={task.isCompleted}>{task.title}</p>
-					{#if task.dueDate}
-						<p class="task-due">{new Date(task.dueDate).toLocaleDateString('de')}</p>
+					{#if task.dueDate || taskTags.length > 0}
+						<div class="task-meta">
+							{#if task.dueDate}
+								<span class="task-due">{new Date(task.dueDate).toLocaleDateString('de')}</span>
+							{/if}
+							{#each taskTags as tag (tag.id)}
+								<span class="tag-dot" style="background: {tag.color}" title={tag.name}></span>
+							{/each}
+						</div>
 					{/if}
 				</div>
 			</button>
@@ -282,10 +312,26 @@
 	:global(.dark) .task-title.completed {
 		color: #6b7280;
 	}
+	.task-meta {
+		display: flex;
+		align-items: center;
+		gap: 0.375rem;
+		margin: 0;
+	}
 	.task-due {
 		font-size: 0.6875rem;
 		color: #9ca3af;
-		margin: 0;
+	}
+	.tag-dot {
+		width: 6px;
+		height: 6px;
+		border-radius: 9999px;
+		flex-shrink: 0;
+	}
+	:global(.task-item.mana-drop-target-hover) {
+		outline: 2px solid rgba(139, 92, 246, 0.4);
+		outline-offset: -2px;
+		background: rgba(139, 92, 246, 0.06) !important;
 	}
 	.empty {
 		padding: 2rem 0;

apps/manacore/apps/web/src/routes/(app)/+page.svelte

@@ -4,6 +4,19 @@
 	import { PageCarousel, type CarouselPage } from '$lib/components/page-carousel';
 	import { getAppEntry } from '$lib/components/workbench/app-registry';
 	import { createAppSettingsStore } from '@manacore/shared-stores';
+	import { DragPreview, dragSource } from '@manacore/shared-ui/dnd';
+	import { useAllTags } from '$lib/stores/tags.svelte';
+	import type { Tag } from '@manacore/shared-tags';
+
+	// ── Tags for drag & drop ───────────────────────────────
+	const allTags$ = useAllTags();
+	let allTags = $state<Tag[]>([]);
+	$effect(() => {
+		const sub = allTags$.subscribe((val) => {
+			allTags = val ?? [];
+		});
+		return () => sub.unsubscribe();
+	});
 
 	// ── Persisted workbench state ───────────────────────────
 	const DEFAULT_WIDTH = 480;
@@ -131,7 +144,26 @@
 	<title>Home - ManaCore</title>
 </svelte:head>
 
+<DragPreview />
+
 <div class="workbench">
+	{#if allTags.length > 0}
+		<div class="tag-bar">
+			{#each allTags as tag (tag.id)}
+				<button
+					class="tag-pill"
+					use:dragSource={{
+						type: 'tag',
+						data: () => ({ id: tag.id, name: tag.name, color: tag.color }),
+					}}
+				>
+					<span class="tag-dot" style="background: {tag.color}"></span>
+					{tag.name}
+				</button>
+			{/each}
+		</div>
+	{/if}
+
 	<PageCarousel
 		pages={carouselPages}
 		defaultWidth={DEFAULT_WIDTH}
@@ -172,4 +204,51 @@
 		flex-direction: column;
 		position: relative;
 	}
+
+	.tag-bar {
+		display: flex;
+		flex-wrap: wrap;
+		gap: 0.375rem;
+		padding: 0.5rem 1rem 0.25rem;
+	}
+	.tag-pill {
+		display: inline-flex;
+		align-items: center;
+		gap: 0.25rem;
+		padding: 0.1875rem 0.5rem;
+		border-radius: 9999px;
+		border: none;
+		background: rgba(0, 0, 0, 0.04);
+		font-size: 0.6875rem;
+		color: #6b7280;
+		cursor: grab;
+		transition: all 0.15s;
+		user-select: none;
+		touch-action: none;
+	}
+	.tag-pill:hover {
+		background: rgba(0, 0, 0, 0.08);
+		color: #374151;
+	}
+	:global(.dark) .tag-pill {
+		background: rgba(255, 255, 255, 0.06);
+		color: #9ca3af;
+	}
+	:global(.dark) .tag-pill:hover {
+		background: rgba(255, 255, 255, 0.1);
+		color: #e5e7eb;
+	}
+	.tag-pill:active {
+		cursor: grabbing;
+	}
+	:global(.tag-pill.mana-drag-source-active) {
+		opacity: 0.4;
+		transform: scale(0.95);
+	}
+	.tag-dot {
+		width: 6px;
+		height: 6px;
+		border-radius: 9999px;
+		flex-shrink: 0;
+	}
 </style>