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## Summary by CodeRabbit
* **New Features**
* Introduced a new mobile journals page with a two-step confirmation
flow, allowing users to select a date and confirm before creating or
opening a journal.
* Added a dedicated route for journals on mobile devices.
* Implemented a placeholder view when no journal exists for a selected
date on both desktop and mobile.
* **Enhancements**
* Improved mobile and desktop styling for journals pages, including
responsive adjustments for mobile layouts.
* Updated journal navigation behavior based on a feature flag, enabling
or disabling the two-step confirmation flow.
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