test: red executable-spec for #266 — aura --version carries the engine commit

aura --version must print 'aura 0.1.0 (<commit>)', the commit sourced
from the same AURA_COMMIT build provenance the run manifest stamps —
a pre-run freshness probe distinguishing a stale binary from an engine
bug. Fails on the absent parenthesized commit, not on scaffolding.

refs #266

crates/aura-cli/tests/cli_run.rs

@@ -4866,6 +4866,42 @@ fn version_flag_prints_version_to_stdout_and_exits_zero() {
     }
 }
 
+/// `--version` carries the ENGINE COMMIT beside the semver, drawn from the SAME
+/// `AURA_COMMIT` build-time provenance the run manifest stamps (the
+/// `option_env!("AURA_COMMIT")` that fills `RunManifest.commit`), so a stale
+/// binary is distinguishable at the CLI surface *before* any run (#266). Shape:
+/// `aura 0.1.0 (<commit-ish>)`, exit 0.
+///
+/// Property, not a specific sha: the expected commit is read from the same
+/// provenance source the built binary was compiled with — this integration test
+/// receives aura-cli's build-script `rustc-env`, so it sees the identical value
+/// (dirty/`unknown` suffixes included) rather than today's HEAD, keeping the
+/// assertion honest against a lagging or unclean tree. The load-bearing claim is
+/// that the parenthesized commit rides beside the still-present semver.
+#[test]
+fn version_flag_carries_the_engine_commit_from_manifest_provenance() {
+    // The single source of truth — the same env the manifest's commit is sourced
+    // from; falls back to "unknown" identically to `sim_optimal_manifest`.
+    let commit = option_env!("AURA_COMMIT").unwrap_or("unknown");
+    let out = std::process::Command::new(env!("CARGO_BIN_EXE_aura"))
+        .arg("--version")
+        .output()
+        .expect("spawn aura");
+    assert_eq!(out.status.code(), Some(0), "--version exit {:?}", out.status);
+    let stdout = String::from_utf8_lossy(&out.stdout);
+    // Semver stays present (one source of truth, CARGO_PKG_VERSION).
+    assert!(
+        stdout.contains(env!("CARGO_PKG_VERSION")),
+        "--version still prints the semver: {stdout:?}"
+    );
+    // ...and the engine commit rides beside it, parenthesized, from the shared
+    // manifest provenance — the load-bearing assertion #266 adds.
+    assert!(
+        stdout.contains(&format!("({commit})")),
+        "--version prints the engine commit ({commit}) beside the semver: {stdout:?}"
+    );
+}
+
 /// Subcommand help is SCOPED: `aura sweep --help` names sweep's own flags and is
 /// NOT byte-identical to `aura run --help` — each subcommand documents its own
 /// options rather than reprinting one shared global blob (the #131 uniform-help