Add Threat Hunt and Rules Engine cards to main page

- Add new Advanced Capabilities section with two centered cards
- Threat Hunt: detection rule generation and hunt package management
- Rules Engine: hypothesis evaluation with confidence scoring and audit trail

https://claude.ai/code/session_01FUJQyGdWpZSgYkW1Xb95gU

Author: claude

docs/index.html

@@ -85,6 +85,14 @@ <h2>Start here by role</h2>
       </div>
     </section>
 
+    <section>
+      <h2>Advanced Capabilities</h2>
+      <div class="grid" style="max-width: 600px; margin-left: auto; margin-right: auto;">
+        <div class="card"><h3>Threat Hunt</h3><p>Convert STIX indicators to Sigma, YARA, Suricata, and Snort rules. Track hunt effectiveness and auto-archive stale rules.</p></div>
+        <div class="card"><h3>Rules Engine</h3><p>Evaluate threat hypotheses with weighted confidence scoring. Hy + YAML declarative rules. Audit trail for all intelligence decisions.</p></div>
+      </div>
+    </section>
+
     <section>
       <h2>The GNAT-o-sphere</h2>
       <div class="grid">