refactor(ui): unify LanguageSelector, ConfirmDialog, and AppSlider across apps

- contacts, zitare: migrate LanguageSelector to shared PillDropdown pattern
- context, times: replace local ConfirmDialog with ConfirmationModal from @manacore/shared-ui
  - delete local ConfirmDialog.svelte in both apps
  - map open→visible, onCancel→onClose, remove destructive prop (default in shared-ui)
- calendar, chat, contacts, presi, todo: switch AppSlider from static MANA_APPS
  to getActiveManaApps() to filter inactive apps consistently

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

apps/context/apps/web/src/lib/components/ConfirmDialog.svelte

@@ -1,48 +0,0 @@
-<script lang="ts">
-	interface Props {
-		open: boolean;
-		title: string;
-		message: string;
-		confirmLabel?: string;
-		cancelLabel?: string;
-		destructive?: boolean;
-		onConfirm: () => void;
-		onCancel: () => void;
-	}
-
-	let {
-		open,
-		title,
-		message,
-		confirmLabel = 'Bestätigen',
-		cancelLabel = 'Abbrechen',
-		destructive = false,
-		onConfirm,
-		onCancel,
-	}: Props = $props();
-</script>
-
-{#if open}
-	<div class="fixed inset-0 z-50 flex items-center justify-center" role="dialog" aria-modal="true">
-		<button class="absolute inset-0 bg-black/50" onclick={onCancel} aria-label="Schließen"></button>
-		<div
-			class="relative bg-card border border-border rounded-xl p-6 max-w-sm w-full mx-4 shadow-xl"
-		>
-			<h3 class="text-lg font-semibold text-foreground">{title}</h3>
-			<p class="text-sm text-muted-foreground mt-2">{message}</p>
-			<div class="flex justify-end gap-2 mt-6">
-				<button class="btn btn-secondary text-sm" onclick={onCancel}>
-					{cancelLabel}
-				</button>
-				<button
-					class="btn text-sm text-white {destructive
-						? 'bg-destructive hover:bg-destructive/90'
-						: 'btn-primary'}"
-					onclick={onConfirm}
-				>
-					{confirmLabel}
-				</button>
-			</div>
-		</div>
-	</div>
-{/if}

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

@@ -11,7 +11,7 @@
 		getAllDocumentTags,
 	} from '$lib/data/queries';
 	import DocumentCard from '$lib/components/DocumentCard.svelte';
-	import ConfirmDialog from '$lib/components/ConfirmDialog.svelte';
+	import { ConfirmationModal } from '@manacore/shared-ui';
 	import type { DocumentType } from '$lib/types';
 
 	let deleteTarget = $state<string | null>(null);
@@ -190,12 +190,11 @@
 	{/if}
 </div>
 
-<ConfirmDialog
-	open={deleteTarget !== null}
+<ConfirmationModal
+	visible={deleteTarget !== null}
 	title="Dokument löschen?"
 	message="Das Dokument wird unwiderruflich gelöscht."
 	confirmLabel="Löschen"
-	destructive
 	onConfirm={handleDeleteConfirm}
-	onCancel={() => (deleteTarget = null)}
+	onClose={() => (deleteTarget = null)}
 />

apps/context/apps/web/src/routes/(app)/documents/[id]/+page.svelte

@@ -9,7 +9,7 @@
 	import { tokensStore } from '$lib/stores/tokens.svelte';
 	import DocumentEditor from '$lib/components/DocumentEditor.svelte';
 	import AIToolbar from '$lib/components/AIToolbar.svelte';
-	import ConfirmDialog from '$lib/components/ConfirmDialog.svelte';
+	import { ConfirmationModal } from '@manacore/shared-ui';
 	import type { Document, DocumentType } from '$lib/types';
 	import type { InsertionMode } from '$lib/services/ai';
 
@@ -164,12 +164,11 @@
 	{/if}
 </div>
 
-<ConfirmDialog
-	open={showDeleteConfirm}
+<ConfirmationModal
+	visible={showDeleteConfirm}
 	title="Dokument löschen?"
 	message="Das Dokument wird unwiderruflich gelöscht."
 	confirmLabel="Löschen"
-	destructive
 	onConfirm={handleDelete}
-	onCancel={() => (showDeleteConfirm = false)}
+	onClose={() => (showDeleteConfirm = false)}
 />

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

@@ -6,7 +6,7 @@
 	import { useAllSpaces } from '$lib/data/queries';
 	import SpaceCard from '$lib/components/SpaceCard.svelte';
 	import CreateSpaceModal from '$lib/components/CreateSpaceModal.svelte';
-	import ConfirmDialog from '$lib/components/ConfirmDialog.svelte';
+	import { ConfirmationModal } from '@manacore/shared-ui';
 	import type { Space } from '$lib/types';
 
 	let searchQuery = $state('');
@@ -131,12 +131,11 @@
 	onClose={() => (showCreateModal = false)}
 />
 
-<ConfirmDialog
-	open={deleteTarget !== null}
+<ConfirmationModal
+	visible={deleteTarget !== null}
 	title="Space löschen?"
 	message="Alle Dokumente in diesem Space werden ebenfalls gelöscht. Diese Aktion kann nicht rückgängig gemacht werden."
 	confirmLabel="Löschen"
-	destructive
 	onConfirm={handleDeleteConfirm}
-	onCancel={() => (deleteTarget = null)}
+	onClose={() => (deleteTarget = null)}
 />

apps/context/apps/web/src/routes/(app)/spaces/[id]/+page.svelte

@@ -21,7 +21,7 @@
 		findSpaceById,
 	} from '$lib/data/queries';
 	import DocumentCard from '$lib/components/DocumentCard.svelte';
-	import ConfirmDialog from '$lib/components/ConfirmDialog.svelte';
+	import { ConfirmationModal } from '@manacore/shared-ui';
 	import BatchCreateModal from '$lib/components/BatchCreateModal.svelte';
 	import type { Space, DocumentType } from '$lib/types';
 
@@ -270,14 +270,13 @@
 	{/if}
 </div>
 
-<ConfirmDialog
-	open={deleteTarget !== null}
+<ConfirmationModal
+	visible={deleteTarget !== null}
 	title="Dokument löschen?"
 	message="Das Dokument wird unwiderruflich gelöscht."
 	confirmLabel="Löschen"
-	destructive
 	onConfirm={handleDeleteConfirm}
-	onCancel={() => (deleteTarget = null)}
+	onClose={() => (deleteTarget = null)}
 />
 
 <BatchCreateModal