Move package_manifest and package_id into a subdir

src/dds/build.hpp

 #pragma once
 
 #include <dds/build/params.hpp>
-#include <dds/package_manifest.hpp>
+#include <dds/package/manifest.hpp>
 
 namespace dds {
 

src/dds/catalog/catalog.hpp

 
 #include <dds/catalog/git.hpp>
 #include <dds/deps.hpp>
-#include <dds/package_id.hpp>
+#include <dds/package/id.hpp>
 #include <dds/util/fs.hpp>
 
 #include <neo/sqlite3/database.hpp>

src/dds/package_id.cpp → src/dds/package/id.cpp

-#include <dds/package_id.hpp>
+#include <dds/package/id.hpp>
 
 #include <spdlog/fmt/fmt.h>
 

src/dds/package_id.test.cpp → src/dds/package/id.test.cpp

-#include <dds/package_id.hpp>
+#include <dds/package/id.hpp>
 
 #include <catch2/catch.hpp>
 

src/dds/package_manifest.cpp → src/dds/package/manifest.cpp

-#include "./package_manifest.hpp"
+#include "./manifest.hpp"
 
 #include <dds/util/string.hpp>
 #include <libman/parse.hpp>

src/dds/package_manifest.hpp → src/dds/package/manifest.hpp

 #pragma once
 
 #include <dds/deps.hpp>
-#include <dds/package_id.hpp>
+#include <dds/package/id.hpp>
 #include <dds/util/fs.hpp>
 #include <semver/version.hpp>
 

src/dds/sdist.hpp

 
 #include <tuple>
 
-#include <dds/package_manifest.hpp>
+#include <dds/package/manifest.hpp>
 #include <dds/util/fs.hpp>
 
 namespace dds {

src/dds/solve/solve.hpp

 #pragma once
 
 #include <dds/deps.hpp>
-#include <dds/package_id.hpp>
+#include <dds/package/id.hpp>
 
 #include <functional>