Rename project from nginx-test to sqlite-serve

- Updated package name in Cargo.toml: nginx-test → sqlite-serve
- Updated library name: libnginx_test.dylib → libsqlite_serve.dylib
- Updated all load_module directives in nginx configs
- Updated build checks in start scripts
- Updated branding in footer template
- Updated project name in all README files

The name 'sqlite-serve' better reflects the module's purpose:
serving dynamic content from SQLite databases via NGINX.

server_root/global_templates/footer.hbs

@@ -1,6 +1,6 @@
         </main>
         <footer style="background: #f8f9fa; padding: 2rem; text-align: center; border-top: 2px solid #e9ecef; color: #6c757d;">
-            <p>📖 Powered by nginx-test SQLite Module</p>
+            <p>📖 Powered by sqlite-serve</p>
             <p style="margin-top: 0.5rem; font-size: 0.9rem;">A demonstration of Rust + NGINX + SQLite + Handlebars</p>
         </footer>
     </div>