feat(perception): expose active app metadata in UI tree

tests/test_active_app.py

@@ -0,0 +1,54 @@
+from __future__ import annotations
+
+from unittest.mock import MagicMock
+
+from core.models import ActiveApp
+from driver.android_driver import AndroidDriver
+from driver.wda_driver import WDADriver
+from tools.ui_tree import get_ui_tree
+from device.manager import DeviceManager
+from tests.fakes import FakeDriver
+
+
+def test_android_driver_reads_current_package_and_activity() -> None:
+    driver = AndroidDriver()
+    driver._client = MagicMock()
+    driver._client.current_package = "com.example.mobile"
+    driver._client.current_activity = ".MainActivity"
+
+    assert driver.active_app() == ActiveApp(
+        platform="android",
+        package="com.example.mobile",
+        activity=".MainActivity",
+    )
+
+
+def test_wda_driver_reads_current_bundle_id() -> None:
+    driver = WDADriver()
+    driver._client = MagicMock()
+    driver._client.execute_script.return_value = {
+        "bundleId": "com.example.mobile",
+        "pid": 123,
+    }
+
+    assert driver.active_app() == ActiveApp(
+        platform="ios",
+        bundle_id="com.example.mobile",
+    )
+    driver._client.execute_script.assert_called_once_with("mobile: activeAppInfo")
+
+
+def test_ui_tree_keeps_list_response_without_active_app_option() -> None:
+    manager = DeviceManager()
+    manager.register_device(
+        "phone-1",
+        lambda: FakeDriver(
+            active_app=ActiveApp(platform="ios", bundle_id="com.example.mobile")
+        ),
+    )
+    manager.connect("phone-1")
+
+    response = get_ui_tree("phone-1", manager=manager)
+
+    assert isinstance(response, list)
+    assert any(node["text"] == "Search" for node in response)