- update safe checking for string util

- remove required for threshold in joi
-  refine if logic and update no error checking with values due to the change to set null instead of delete error entry
- move customthreshold component to under create infrastructure folder
- correct interval setting and threshold default value and fix typo

Client/src/Utils/stringUtils.js

@@ -3,6 +3,15 @@
  * @param {string} str String whose first letter is to be capitalized
  * @returns A string with first letter capitalized
  */
-export const capitalizeFirstLetter = (str) =>{
-  return  str?.charAt(0).toUpperCase() + str.slice(1);
-}
+export const capitalizeFirstLetter = (str) => {	
+  if (str === null || str === undefined) {
+		return "";
+	}
+	if (typeof str !== "string") {
+		throw new TypeError("Input must be a string");
+	}
+	if (str.length === 0) {
+		return "";
+	}  
+	return str.charAt(0).toUpperCase() + str.slice(1);
+};