DUBAI, United Arab Emirates—A skyscraper-sized container ship has become wedged across Egypt’s Suez Canal and blocked all traffic in the vital waterway, officials said Wednesday, threatening to disrupt a global shipping system already strained by the coronavirus pandemic. The MV Ever Given, a Panama-flagged ship that carries cargo between Asia and Europe, ran aground Tuesday in the narrow, man-made canal dividing continental Africa from the Sinai Peninsula. Images showed the ship’s bow was touching the eastern wall, while its stern looked lodged against the western wall—an extraordinary event that experts said they had never heard of happening before in the canal’s 150-year history. Tugboats strained Wednesday to try to nudge the obstruction out of the way as ships hoping to enter the waterway began lining up in the Mediterranean and Red Seas. But it remained unclear when the route, through which around 10 percent of world trade flows and which …