feat(fase-14): offline chip + queued-op badge in global chrome (14.2.1-2)

Adds an OfflineChip surfaced in the MobileTopBar (compact, icon-only)
and at the bottom of the DesktopSidebar (full pill with label). Hidden
while online. When `navigator.onLine` is false:

  - The chip mounts with the existing amber palette
  - A title tooltip explains the implication ("changes will sync when
    you reconnect")
  - If `pendingOpsCount > 0`, a small numeric badge is appended so the
    user sees the actual backlog size at a glance

`pendingOpsCount` is the existing store (kept in sync by SyncQueue);
nothing new wires up — we only surface what was already tracked.

OF-01 e2e: drives `context.setOffline(true)`, asserts the chip
appears, queues an INSERT, asserts the numeric badge renders, and
verifies the chip disappears when back online. Added alongside the
existing O-01/O-02 (banner-based) so we keep coverage of both surfaces.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

apps/web/src/lib/components/layout/DesktopSidebar.svelte

@@ -7,6 +7,7 @@
 	import type { SectionKey } from '@colectivo/types';
 	import Avatar from '$lib/components/Avatar.svelte';
 	import CreateCollectiveModal from '$lib/components/CreateCollectiveModal.svelte';
+	import OfflineChip from '$lib/components/OfflineChip.svelte';
 	import * as m from '$lib/paraglide/messages';
 	import { ShoppingCart, CheckSquare, FileText, Search, Settings, Plus, Shield } from 'lucide-svelte';
 
@@ -101,6 +102,9 @@
 	</nav>
 
 	<div class="p-3 pt-2">
+		<div class="mb-2 flex justify-end">
+			<OfflineChip />
+		</div>
 		{#if $isServerAdmin}
 			<!-- Fase 13.4: server-admin entry. Distinct red icon so it doesn't
 			     blend with normal app nav. Hidden for non-admins. -->