[FEATURE] Simple User Online Status on Profile Pages

[sanaderi]

Add a simple online status indicator on user profile pages and profile list pages. Status is determined by the user's last login timestamp. No real-time WebSocket required.

Status Types

Last Login	Status Shown
Less than 5 minutes ago	Online
Less than 1 hour ago	Active recently
Less than 24 hours ago	Online today
Less than 7 days ago	Active this week
Less than 30 days ago	Active this month
More than 30 days ago	Last active [date]
Never logged in	New user

Where Status Appears

Individual Profile Page

• Status shown next to user's name or avatar
• Hover or tap shows exact last login time

Profile List Page

• Compact status indicator (colored dot or short text)
• Hover shows exact last login time

Acceptance Criteria

• Status displays on individual profile page
• Status displays on profile list/card page
• Status updates based only on last login time
• Hover or tap shows exact last login timestamp
• New users show appropriate status
• No WebSocket or real-time connections used
• Works for both student and teacher profiles
• Status is visual only with no functional impact