macOS & Web: Toggleable Right‑Side Detail View in Habit List

Problem:
From the Today/All Habits list, you can’t view habit details without opening a separate page.

Suggestion:
Add an optional detail panel on the right showing the selected habit’s information, logs, and notes. Toggle it via a button or shortcut.

Why:

• Faster review and navigation

• Keeps context without page navigation

• Consistent split‑view layout