fix#13531
#### PR Dependency Tree
* **PR #14372** 👈
This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)
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## Summary by CodeRabbit
* **New Features**
* CalDAV calendar integration: link and sync CalDAV-compatible calendars
(discovery, listing, event sync).
* New UI flow and dialog to link CalDAV accounts with provider
selection, credentials, and display name.
* **API / Config**
* Server exposes CalDAV provider presets in config and new GraphQL
mutation to link CalDAV accounts.
* New calendar config section for CalDAV with validation and defaults.
* **Tests**
* Comprehensive CalDAV integration test suite added.
* **Chores**
* Removed analytics tokens from build configuration and reduced Cloud
E2E test shards.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
