test(cli): RED — a fresh scaffold leaves no resolvable HEAD (#243)

aura new git-inits but never commits, so the first run stamps empty
project provenance. RED pin:
new_outside_a_work_tree_leaves_a_resolvable_head.

refs #243

crates/aura-cli/tests/project_new.rs

@@ -220,6 +220,57 @@ fn new_outside_a_work_tree_initializes_git() {
     let _ = std::fs::remove_dir_all(&base);
 }
 
+/// Property (#243): a freshly scaffolded project stamps resolvable
+/// provenance from its very first run. Outside any enclosing work tree
+/// `aura new` owns the scaffold's history, so it must leave the project with
+/// a HEAD — `git rev-parse HEAD` resolves — and the first advertised
+/// quickstart `aura run` therefore stamps a `manifest.project.commit`, rather
+/// than the empty `"project":{}` that a bare `git init` with no commit yields
+/// (a first manifest that is silently un-reproducible-by-commit). This is the
+/// property the neighbouring loop headline can only reach today via a manual
+/// `init_and_commit` on the enclosing tree.
+#[test]
+fn new_outside_a_work_tree_leaves_a_resolvable_head() {
+    let base = tmp("headprov");
+    let out = aura(&["new", "demo-lab"], &base);
+    assert!(
+        out.status.success(),
+        "aura new failed: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    let proj = base.join("demo-lab");
+
+    // The scaffold has its own repo (guarded elsewhere) AND that repo has a
+    // HEAD: `git rev-parse HEAD` resolves. A bare `git init` with no commit
+    // leaves HEAD unborn and this fails.
+    let head = Command::new("git")
+        .args(["rev-parse", "HEAD"])
+        .current_dir(&proj)
+        .output()
+        .expect("run git rev-parse HEAD");
+    assert!(
+        head.status.success(),
+        "fresh scaffold has no HEAD (`git rev-parse HEAD` failed): {}",
+        String::from_utf8_lossy(&head.stderr)
+    );
+
+    // ...so the first quickstart run stamps a commit into the manifest, not
+    // an empty provenance block.
+    let run = aura(&["run", "blueprints/signal.json"], &proj);
+    assert!(
+        run.status.success(),
+        "run failed: {}",
+        String::from_utf8_lossy(&run.stderr)
+    );
+    let v: serde_json::Value = serde_json::from_slice(&run.stdout).expect("report is JSON");
+    let p = &v["manifest"]["project"];
+    assert!(
+        p.get("commit").is_some(),
+        "first run of a fresh scaffold must stamp a commit, not empty provenance: {p}"
+    );
+    let _ = std::fs::remove_dir_all(&base);
+}
+
 #[test]
 fn new_works_inside_an_unbuilt_project_tree() {
     // Scaffold once, then scaffold AGAIN from inside that tree: the