refactor: replace metrics-based tunnel status check with direct status command in is_active function

Replace metrics query in is_active with direct tunnel_backend status command call to avoid unnecessary metrics overhead when only checking tunnel state. Parse status command stdout and compare against "active" string case-insensitively. Add Windows CREATE_NO_WINDOW flag to status command execution.

desktop-client/src-tauri/src/tunnel_manager.rs

@@ -57,7 +57,21 @@ pub fn disconnect(app: &AppHandle, profile_path: &Path) -> Result<(), String> {
 }
 
 pub fn is_active(app: &AppHandle, profile_path: &Path) -> Result<bool, String> {
-    Ok(metrics(app, profile_path)?.active)
+    let backend = bundled_backend(app)?;
+    let mut command = Command::new(backend);
+    command.arg("status").arg("--profile").arg(profile_path);
+    #[cfg(target_os = "windows")]
+    command.creation_flags(CREATE_NO_WINDOW);
+    let output = command
+        .output()
+        .map_err(|err| format!("Unable to query embedded tunnel backend status: {}", err))?;
+
+    if !output.status.success() {
+        return Err(format_helper_error("status", &output));
+    }
+
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    Ok(stdout.trim().eq_ignore_ascii_case("active"))
 }
 
 pub fn metrics(app: &AppHandle, profile_path: &Path) -> Result<TunnelMetrics, String> {