feat: add WebSocket endpoint and ConnectionManager setup

Add WebSocket infrastructure to main server:
- Import sync package for ConnectionManager
- Create and start ConnectionManager with cleanup task
- Initialize WSHandler with auth dependencies
- Add /ws/sync WebSocket endpoint
- Update handler initialization to pass ConnectionManager

The WebSocket endpoint at /ws/sync enables real-time progress
updates across all connected clients (web, mobile, devices).

cmd/server/main.go

@@ -6,6 +6,7 @@ import (
 	"bookmann/internal/handlers"
 	"bookmann/internal/middleware"
 	ratelimit "bookmann/internal/middleware"
+	"bookmann/internal/sync"
 	"bookmann/templates"
 	"bytes"
 	"context"
@@ -50,10 +51,15 @@ func main() {
 	authHandler := handlers.NewAuthHandler(queries, cfg.JWTSecret, loginAttemptTracker)
 	libraryHandler := handlers.NewLibraryHandler(queries)
 	deviceHandler := handlers.NewDeviceHandler(queries, cfg.JWTSecret, cfg)
-	koreaderHandler := handlers.NewKOReaderHandler(queries)
-
 	deviceAuthMiddleware := middleware.NewDeviceAuthMiddleware(queries)
 
+	// Create WebSocket connection manager
+	connManager := sync.NewConnectionManager()
+	connManager.StartCleanupTask()
+
+	koreaderHandler := handlers.NewKOReaderHandler(queries, connManager)
+	wsHandler := handlers.NewWSHandler(queries, connManager, cfg.JWTSecret, deviceAuthMiddleware)
+
 	e := echo.New()
 
 	// Set up validator
@@ -117,7 +123,7 @@ func main() {
 	protected := e.Group("/api", jwtMiddleware)
 
 	// Setup ebook handler routes first (so we can use it for library scan)
-	h := handlers.SetupRoutes(protected, queries)
+	h := handlers.SetupRoutes(protected, queries, connManager)
 
 	// Public library types endpoint (no authentication required)
 	e.GET("/api/libraries/types", libraryHandler.GetLibraryTypes)
@@ -196,6 +202,9 @@ func main() {
 	devices.DELETE("/:id", deviceHandler.DeleteDevice)
 	devices.GET("/pending", deviceHandler.ListPendingRegistrations)
 
+	// WebSocket endpoint for real-time sync
+	e.GET("/ws/sync", wsHandler.HandleWebSocket)
+
 	// Static files
 	e.Static("/static", "web/static")