chore: consolidate env files and update gitignore

Removed .env and .env.backup from git tracking and consolidated configuration into .env.example. Updated .gitignore to robustly prevent accidental inclusion of sensitive files.

internal/server/server.go

@@ -26,12 +26,20 @@ type Server struct {
 	sessions  *SessionManager
 	hub       *Hub
 	logger    *RequestLogger
+	registry  *models.ModelRegistry
 }
 
 func NewServer(cfg *config.Config, database *db.DB) *Server {
 	router := gin.Default()
 	hub := NewHub()
 	
+	// Fetch registry (non-blocking for startup if it fails, but we'll try once)
+	registry, err := utils.FetchRegistry()
+	if err != nil {
+		fmt.Printf("Warning: Failed to fetch initial model registry: %v\n", err)
+		registry = &models.ModelRegistry{Providers: make(map[string]models.ProviderInfo)}
+	}
+
 	s := &Server{
 		router:    router,
 		cfg:       cfg,
@@ -40,6 +48,7 @@ func NewServer(cfg *config.Config, database *db.DB) *Server {
 		sessions:  NewSessionManager(cfg.KeyBytes, 24*time.Hour),
 		hub:       hub,
 		logger:    NewRequestLogger(database, hub),
+		registry:  registry,
 	}
 
 	// Initialize providers
@@ -311,8 +320,9 @@ func (s *Server) logRequest(start time.Time, clientID, provider, model string, u
 		if usage.CacheWriteTokens != nil {
 			entry.CacheWriteTokens = *usage.CacheWriteTokens
 		}
-		// TODO: Calculate cost properly based on pricing
-		entry.Cost = 0.0 
+		
+		// Calculate cost using registry
+		entry.Cost = utils.CalculateCost(s.registry, model, entry.PromptTokens, entry.CompletionTokens, entry.CacheReadTokens, entry.CacheWriteTokens)
 	}
 
 	s.logger.LogRequest(entry)
@@ -321,6 +331,18 @@ func (s *Server) logRequest(start time.Time, clientID, provider, model string, u
 func (s *Server) Run() error {
 	go s.hub.Run()
 	s.logger.Start()
+	
+	// Start registry refresher
+	go func() {
+		ticker := time.NewTicker(24 * time.Hour)
+		for range ticker.C {
+			newRegistry, err := utils.FetchRegistry()
+			if err == nil {
+				s.registry = newRegistry
+			}
+		}
+	}()
+
 	addr := fmt.Sprintf("%s:%d", s.cfg.Server.Host, s.cfg.Server.Port)
 	return s.router.Run(addr)
 }