Add release notes for 1.3.0

[opatry]

Description

• Enable task move actions (to top, to list, to new list)
• Support subtask creation
• Allow setting due dates directly from a task cell
• Fix 1-day offset issue in the date picker
• Add support for sorting tasks by title
• Enhance task sorting functionality
• Introduce “Per-app language preferences” on Android
• General performance improvements and under-the-hood optimizations

Checklist

• I have read the CONTRIBUTING guide
• Code compiles correctly
• Created tests which fail without the change (if possible)
• All tests passing