Description

The backend currently fails to compile due to several syntax errors, duplicate declarations, and unresolved merge conflicts.

Issues Identified

1. Config Redefinition: backend/config/config.go contains a duplicate definition of the Redis struct field.
2. Model Collision: backend/models/admin.go defines a Comment struct that conflicts with the Comment struct in backend/models/comment.go, causing "redeclare" errors.
3. Missing Imports: backend/db/db.go is missing the log import.
4. Merge Conflicts: backend/websocket/team_websocket.go contains unresolved git merge conflict markers (<<<< HEAD).
5. Gemini Service: The backend/services/gemini.go file references undefined clients/methods and uses an incorrect import/implementation mix for the Gemini SDK.

Goal

Fix all build errors so the backend server can start successfully (go run cmd/server/main.go).