feat: add managed accessibility helper with UIAutomator fallback

tests/unit/runtime/test_helper_bundle.py

@@ -0,0 +1,52 @@
+"""The bundled helper APK, its manifest, and the Gradle version must agree.
+
+``helper_manager`` decides installs and upgrades from ``helper_manifest.json``,
+so a rebuilt APK without a regenerated manifest (or a version bump in Gradle
+without a rebuild) would silently ship the wrong version gate.
+"""
+
+from __future__ import annotations
+
+import hashlib
+import json
+import re
+
+import pytest
+
+from artemis.runtime.helper_manager import (
+    BUNDLED_APK_PATH,
+    BUNDLED_MANIFEST_PATH,
+    HELPER_PACKAGE_DIR,
+    PACKAGE_NAME,
+    load_bundled_helper,
+)
+
+pytestmark = pytest.mark.skipif(
+    not BUNDLED_APK_PATH.is_file(), reason="bundled helper APK is not present in this checkout"
+)
+
+
+def test_manifest_matches_apk_and_gradle_version():
+    manifest = json.loads(BUNDLED_MANIFEST_PATH.read_text(encoding="utf-8"))
+    assert manifest["package"] == PACKAGE_NAME
+    assert manifest["sha256"] == hashlib.sha256(BUNDLED_APK_PATH.read_bytes()).hexdigest(), (
+        "ArtemisAccessibilityHelper.apk was rebuilt without regenerating helper_manifest.json; "
+        "run packages/artemis-accessibility-helper/build_apk.sh"
+    )
+
+    gradle = (HELPER_PACKAGE_DIR / "app" / "build.gradle.kts").read_text(encoding="utf-8")
+    version_code = int(re.search(r"versionCode\s*=\s*(\d+)", gradle).group(1))
+    version_name = re.search(r'versionName\s*=\s*"([^"]+)"', gradle).group(1)
+    assert manifest["version_code"] == version_code
+    assert manifest["version_name"] == version_name
+
+
+def test_load_bundled_helper_reads_manifest():
+    bundled = load_bundled_helper()
+    assert bundled is not None
+    assert bundled.apk_path == BUNDLED_APK_PATH
+    assert bundled.version_code >= 2  # first version that reports version_code on /ping
+
+
+def test_load_bundled_helper_returns_none_when_missing(tmp_path):
+    assert load_bundled_helper(tmp_path / "x.apk", tmp_path / "x.json") is None