The International Monetary Fund said on Tuesday that the pace of the global economic recovery is slowing, a warning that came as a new war in the Middle East threatened to upend a world economy already reeling from several years of overlapping crises. The eruption of fighting between Israel and Hamas over the weekend, which could sow disruption across the region, reflects how challenging it has become to shield economies from increasingly frequent and unpredictable global shocks. The conflict has cast a cloud over a gathering of top economic policymakers…