Move/strong username regex (#2070)

* Update and rename Script.js to Script.js

Moved to Regex folder and added comment to explain the Regex.

* Update and rename README.md to README.md

Updated the readme to be more descriptive: described the criteria the script evaluates, and added how to use the script.

Author: WillemZeiler

Client-Side Components/Catalog Client Script/Strong Username Validation Script/README.md

@@ -0,0 +1,10 @@
+## Strong Username Validation Script
+This script validates a username entered in a ServiceNow catalog item form. It prevents form submission if the username does not meet the required format.
+
+### Validation Criteria
+The username must start with a letter (a–z or A–Z).
+It must be at least 6 characters long.
+It can only contain letters and numbers.
+
+## Usage
+Add the script as an onSubmit client script in the catalog item. If the username is invalid, an error message is shown and the form is not submitted.

Specialized Areas/Regular Expressions/Username validation/README.md

@@ -4,6 +4,14 @@ function onSubmit() {
 
     // Define the regex pattern for a strong username
     var usernamePattern = /^[a-zA-Z][a-zA-Z0-9]{5,}$/;
+    
+    // Regex explanation:
+    // ^           : Start of string
+    // [a-zA-Z]    : First character must be a letter
+    // [a-zA-Z0-9] : Remaining characters can be letters or digits
+    // {5,}        : At least 5 more characters (total minimum length = 6)
+    // $           : End of string
+
 
     // Validate the username against the pattern
     if (!usernamePattern.test(username)) {