Add free Resources page: Civilian Zero Trust series

Publishes the three-part Civilian Zero Trust series (Primer, Phase One,
Phase Two) as free advisory content at /resources/, with accessible
PDF/UA-1 downloads. Adds a Resources nav link to the homepage and
Foundation page.

Source docs: about/identity sections rewritten to represent Houston Labs
as the technological R&D company it is (not a 'security publisher'), framing
the series as part of its free advisory and education work.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

index.html

@@ -42,6 +42,7 @@
         <a href="#focus">Focus</a>
         <a href="#approach">Approach</a>
         <a href="foundation/">Foundation</a>
+        <a href="resources/">Resources</a>
         <a href="#contact">Contact</a>
         <a class="nav-pill" href="mailto:contact@houstonlabs.us">Email&nbsp;us</a>
       </div>