Revert "fix: add type safety for tool output schemas in ToolCallback"

src/server/mcp.test.ts

@@ -1312,7 +1312,7 @@ describe("tool()", () => {
           resultType: "structured",
           // Missing required 'timestamp' field
           someExtraField: "unexpected" // Extra field not in schema
-        } as unknown as { processedInput: string; resultType: string; timestamp: string }, // Type assertion to bypass TypeScript validation for testing purposes
+        },
       })
     );