Fix/http node timeout validation#23077 (#23117)

Co-authored-by: crazywoola <427733928@qq.com>

web/app/components/workflow/nodes/http/components/timeout/index.tsx

   description: string
   placeholder: string
   value?: number
-  onChange: (value: number) => void
+  onChange: (value: number | undefined) => void
   readOnly?: boolean
   min: number
   max: number
         type='number'
         value={value}
         onChange={(e) => {
-          const value = Math.max(min, Math.min(max, Number.parseInt(e.target.value, 10)))
-          onChange(value)
+          const inputValue = e.target.value
+          if (inputValue === '') {
+            // When user clears the input, set to undefined to let backend use default values
+            onChange(undefined)
+          }
+          else {
+            const parsedValue = Number.parseInt(inputValue, 10)
+            if (!Number.isNaN(parsedValue)) {
+              const value = Math.max(min, Math.min(max, parsedValue))
+              onChange(value)
+            }
+          }
         }}
         placeholder={placeholder}
         readOnly={readOnly}