The Federal Reserve is an institution that relies on confidence and consistency. Both have been shaken as the agency struggles to tamp down inflation and regain the trust of investors. Central bankers gather in Washington in the week ahead for a regularly scheduled interest rate setting meeting. The group will raise its target short-term borrowing rate again, and it’s likely to be a hike of another three-quarters of a percentage point. But there’s a chance the bankers could go even bigger. Any rate hike will bring the Fed’s interest rate to its highest level since 2008. A one percentage point …