fix(analytics): totalFollows now counts followers received, not follows performed

[Srejoye]

Summary

Fixes #435

The totalFollows field in GET /api/analytics/overview was querying FollowLog with followerId: userId, which counts follows the authenticated user performed on others — the exact opposite of what the dashboard intends to show.

Changes

• Extract username from the JWT payload alongside the existing id
• Replace the followLog.count filter to use targetUsername: username so the metric reflects how many other users have successfully followed the current user
• No response shape change — totalFollows field name is preserved; its semantic is now correct

Testing

• Existing analytics tests updated to assert inbound-follow semantics
• Added seed fixture: User A follows authenticated user (counted), authenticated user follows User B (must not be counted)
• Verified totalFollows returns 0 when no one has followed the user, even if the user has followed many others

Notes

The JWT payload already includes username (set in both authRoutes and connectRoutes at sign time), so no auth changes are required.