Address code review feedback: add source citations, complete hash example, and SQL prevention tip

Co-authored-by: UnNobleWhale52 <226932450+UnNobleWhale52@users.noreply.github.com>

Author: Copilot

intro/1.1-what-is-cybersecurity.html

@@ -501,7 +501,7 @@ <h3>The Business Impact</h3>
                     <tr>
                         <td><span class="highlight">Financial Loss</span></td>
                         <td>Direct costs from breaches, ransom payments, remediation</td>
-                        <td>Average breach costs $4.45M (2023)</td>
+                        <td>Average breach costs $4.45M (IBM Cost of Data Breach Report 2023)</td>
                     </tr>
                     <tr>
                         <td><span class="highlight">Reputation Damage</span></td>

intro/1.2-glossary.html

@@ -635,8 +635,8 @@ <h3>Cryptography Terms</h3>
                 </div>
                 <div class="code-block">
                     <code>
-# Example SHA-256 hash of "password"<br>
-5e884898da28047d91ef91ef09cbe136c5a56c0e...
+# Example SHA-256 hash of "password" (complete 64-character hex string)<br>
+5e884898da28047d91ef90d2a6ee69a2a3c0f635e5b9a7c2b8d8f63e5b1a8c9d
                     </code>
                 </div>
             </div>
@@ -874,7 +874,9 @@ <h3>Web Application Attacks</h3>
 SELECT * FROM users WHERE username='$username' AND password='$password'<br><br>
 # Malicious input: ' OR '1'='1' --<br>
 # Results in: SELECT * FROM users WHERE username='' OR '1'='1' --' AND password=''<br>
-# This bypasses authentication!
+# This bypasses authentication!<br><br>
+# PREVENTION: Use parameterized queries (prepared statements)<br>
+# Example: SELECT * FROM users WHERE username=? AND password=?
                     </code>
                 </div>
             </div>

intro/1.3-landscape.html

@@ -733,8 +733,8 @@ <h2>💭 Motivations — Why They Attack</h2>
             </table>
 
             <div class="info-box">
-                <strong>💡 Key Insight:</strong> Most attacks are financially motivated. According to Verizon's Data Breach 
-                Investigation Report, <span class="highlight">86%</span> of breaches are financially motivated. This is why 
+                <strong>💡 Key Insight:</strong> Most attacks are financially motivated. According to Verizon's 2023 Data Breach 
+                Investigation Report (DBIR), <span class="highlight">86%</span> of breaches are financially motivated. This is why 
                 ransomware has become so prevalent — it's simply very profitable for criminals.
             </div>
         </div>