refactor: inject ConnectionManager into Worker

Pass ConnectionManager to Worker constructor to enable WebSocket
broadcasting capabilities. Updated:
- main.go: server initialization
- test_helpers.go: test setup
- commonhandlers.go: handler initialization

This change enables Worker to broadcast job updates to connected clients.

internal/handlers/commonhandlers.go

@@ -32,7 +32,7 @@ type Handler struct {
 
 func NewHandler(db *database.Queries, connManager *wsync.ConnectionManager, queueProcessor *wsync.SyncQueueProcessor, cfg *config.Config) *Handler {
 	ctx, cancel := context.WithCancel(context.Background())
-	worker := services.NewWorker(3)
+	worker := services.NewWorker(3, connManager)
 
 	queueCtx, queueCancel := context.WithCancel(context.Background())