asset changes

interfaces/Crafter.Build-External.cppm

@@ -97,4 +97,14 @@ export namespace Crafter {
     // recursively LoadProject's it. Returns a stable Configuration* owned
     // by the same internal cache as GitProject.
     CRAFTER_API Configuration* LocalProject(const LocalProjectSpec& spec);
+
+    // Clone (or update) the given git source into the shared external
+    // cache and return the path to the cloned working tree. Intended for
+    // example projects that need large asset bundles which shouldn't
+    // live in the parent repo — push the returned path (or specific
+    // files inside it) into `cfg.assets`. Reuses the same cache root as
+    // ExternalDependency / GitProject. Caching key = url + branch + commit;
+    // identical calls reuse the existing clone. Pin `source.commit` to a
+    // SHA for reproducible, offline-after-first-fetch builds.
+    CRAFTER_API fs::path GitFetch(const GitSource& source);
 }