Add @manacore/shared-links to Calendar, Contacts, and ManaCore apps.
Link store initializes alongside tag store in each app's layout, syncs
when authenticated, and is ready for cross-app linking.
Also fix broken workspace references in moodlit (shared-feedback-service
→ feedback, shared-feedback-ui removed, shared-subscription-ui →
subscriptions).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
