fix(calendar): keep real events when switching day/week view

[MegaBadCoder]

Summary

• Day view opens on today (if it is in the visible week), not the viewport center
• Switching back to week restores the previous scroll instead of jumping to that center day
• Recurring tasks no longer render as ghosts after День ↔ Неделя

Test plan

• Week view with recurring tasks due today — they are solid, not dashed
• Switch to День — same tasks stay solid on today
• Switch back to Неделя — still solid, week position unchanged
• In day view, step to another day then back to week — lands on the original week if that day is still in range

Made with Cursor