Update: 将子项目从 submodule 转为完整内容

- 移除 GovAI, nomifun-tauri, 算力盒子 的 submodule 引用
- 添加所有子项目的完整源代码
- 保留原始 .git 为 .git.bak 备份

nomifun-tauri/crates/backend/nomifun-app/tests/startup_smoke.rs

@@ -0,0 +1,43 @@
+//! Smoke test: starting the app twice with the same binary version
+//! should be a no-op on the second run (version gate skips rewrite).
+
+use tempfile::TempDir;
+
+#[tokio::test]
+async fn second_start_with_same_version_is_noop() {
+    let tmp = TempDir::new().unwrap();
+    let data_dir = tmp.path();
+
+    let first =
+        nomifun_extension::materialize_if_needed(data_dir, nomifun_extension::builtin_skills_corpus(), "test-1.0.0")
+            .await
+            .unwrap();
+    assert!(first, "first call should materialize");
+
+    let second =
+        nomifun_extension::materialize_if_needed(data_dir, nomifun_extension::builtin_skills_corpus(), "test-1.0.0")
+            .await
+            .unwrap();
+    assert!(!second, "second call with same version should skip");
+}
+
+#[tokio::test]
+async fn version_bump_triggers_rewrite() {
+    let tmp = TempDir::new().unwrap();
+    let data_dir = tmp.path();
+
+    let first =
+        nomifun_extension::materialize_if_needed(data_dir, nomifun_extension::builtin_skills_corpus(), "test-1.0.0")
+            .await
+            .unwrap();
+    assert!(first);
+
+    let second =
+        nomifun_extension::materialize_if_needed(data_dir, nomifun_extension::builtin_skills_corpus(), "test-2.0.0")
+            .await
+            .unwrap();
+    assert!(second, "version change should trigger a fresh materialize");
+
+    let version = std::fs::read_to_string(data_dir.join("builtin-skills").join(".version")).unwrap();
+    assert_eq!(version, "test-2.0.0");
+}