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.

start_book_detail.sh

@@ -14,7 +14,7 @@ if [ ! -f "book_catalog.db" ]; then
 fi
 
 # Check if module is built
-if [ ! -f "target/debug/libnginx_test.dylib" ]; then
+if [ ! -f "target/debug/libsqlite_serve.dylib" ]; then
     echo "Module not built. Building..."
     direnv exec "$PWD" cargo build
     echo ""