feat(theme): link footer "Netdocs" text to project docs

The footer credit now links "Netdocs" to the published Netdocs
documentation site so readers can find the generator behind the site.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: Netdocs

src/Netdocs.Theme.Material/templates/partials/footer.html

@@ -29,7 +29,7 @@
     <div class="md-footer-meta__inner md-grid">
       <div class="md-copyright">
         {{~ if config.copyright ~}}<div class="md-copyright__highlight">{{ config.copyright }}</div>{{~ end ~}}
-        Built with Netdocs, a derivative of <a href="https://github.com/squidfunk/mkdocs-material" target="_blank" rel="noopener">MkDocs-Material</a>
+        Built with <a href="https://xtremeownage.github.io/Netdocs" target="_blank" rel="noopener">Netdocs</a>, a derivative of <a href="https://github.com/squidfunk/mkdocs-material" target="_blank" rel="noopener">MkDocs-Material</a>
         {{~ if extra.footer_links ~}}
         <nav class="md-footer-links" aria-label="Footer links">
           {{~ for l in extra.footer_links ~}}