update sidebar header

Author: eiman-eltigani-ttd

tools/hashing-tool/index.html

@@ -223,7 +223,7 @@ <h4>Privacy & Security</h4>
         </div>
 
         <div class="section">
-          <h4>Normalization Matters</h4>
+          <h4>Normalization is Required</h4>
           <ul>
             <li>Ensures consistent ${IDENTITY_NAME}s across systems</li>
             <li><strong>Email:</strong> Lowercase, trim spaces, Gmail special handling</li>