feat(driver): add Android UiAutomator2 driver

Register `SUPPORTED_DRIVER_TYPES["uiautomator2"]` backed by the new
`AndroidDriver`, mirroring `WDADriver` method-for-method. tap/swipe/home use
the confirmed UiAutomator2 mobile commands (`clickGesture`, `dragGesture`,
`pressKey`); swipe converts `duration_ms` to a drag speed with a zero-distance
guard. Adds 34 mocked unit tests, an env-var-gated integration test, and
corrects the outdated "Android not registered" note in the iPhone setup doc.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

driver/android_driver.py

@@ -0,0 +1,188 @@
+from __future__ import annotations
+
+import math
+from dataclasses import dataclass, field
+from typing import Any
+
+from core.errors import DeviceOfflineError, DriverError
+from driver.base import Driver
+
+# Android KeyEvent.KEYCODE_HOME. Kept as a literal rather than importing the
+# full keycode table because this is the only keycode the Driver ABC exposes.
+_KEYCODE_HOME = 3
+
+# Default drag speed (pixels/second) used by ``swipe`` when the caller's start
+# and end coordinates collapse to a zero/near-zero distance, where converting
+# ``duration_ms`` via ``distance / seconds`` would divide by zero.
+_DEFAULT_DRAG_SPEED_PX_PER_SEC = 2500
+
+
+@dataclass(frozen=True)
+class AndroidDriverConfig:
+    server_url: str = "http://127.0.0.1:4723"
+    platform_name: str = "Android"
+    automation_name: str = "UiAutomator2"
+    device_name: str | None = None
+    udid: str | None = None
+    system_port: int | None = None
+    no_reset: bool = True
+    extra_capabilities: dict[str, Any] = field(default_factory=dict)
+
+
+class AndroidDriver(Driver):
+    def __init__(self, config: AndroidDriverConfig | None = None) -> None:
+        self.config = config or AndroidDriverConfig()
+        self._client: Any | None = None
+
+    def connect(self) -> None:
+        try:
+            from appium import webdriver
+            from appium.options.android import UiAutomator2Options
+            from appium.webdriver.client_config import AppiumClientConfig
+        except ImportError as exc:
+            raise DriverError("Appium Python client is not installed") from exc
+
+        capabilities: dict[str, Any] = {
+            "platformName": self.config.platform_name,
+            "automationName": self.config.automation_name,
+            "noReset": self.config.no_reset,
+            **self.config.extra_capabilities,
+        }
+        if self.config.device_name:
+            capabilities["deviceName"] = self.config.device_name
+        if self.config.udid:
+            capabilities["udid"] = self.config.udid
+        if self.config.system_port:
+            capabilities["systemPort"] = self.config.system_port
+
+        options = UiAutomator2Options().load_capabilities(capabilities)
+        client_config = AppiumClientConfig(remote_server_addr=self.config.server_url)
+        try:
+            self._client = webdriver.Remote(
+                options=options,
+                client_config=client_config,
+            )
+        except Exception as exc:
+            self._client = None
+            raise DeviceOfflineError("device offline") from exc
+
+    def disconnect(self) -> None:
+        client = self._require_client()
+        try:
+            client.quit()
+        finally:
+            self._client = None
+
+    def screenshot(self) -> bytes:
+        client = self._require_client()
+        try:
+            return client.get_screenshot_as_png()
+        except Exception as exc:
+            raise DriverError("screenshot failed") from exc
+
+    def tap(self, x: float, y: float) -> None:
+        client = self._require_client()
+        try:
+            client.execute_script("mobile: clickGesture", {"x": x, "y": y})
+        except Exception as exc:
+            raise DriverError("tap failed") from exc
+
+    def swipe(
+        self,
+        start_x: float,
+        start_y: float,
+        end_x: float,
+        end_y: float,
+        duration_ms: int = 500,
+    ) -> None:
+        client = self._require_client()
+        speed = _drag_speed(start_x, start_y, end_x, end_y, duration_ms)
+        try:
+            client.execute_script(
+                "mobile: dragGesture",
+                {
+                    "startX": start_x,
+                    "startY": start_y,
+                    "endX": end_x,
+                    "endY": end_y,
+                    "speed": speed,
+                },
+            )
+        except Exception as exc:
+            raise DriverError("swipe failed") from exc
+
+    def input(self, text: str) -> None:
+        client = self._require_client()
+        try:
+            client.switch_to.active_element.send_keys(text)
+        except Exception as exc:
+            raise DriverError("text input failed") from exc
+
+    def launch(self, app_id: str) -> None:
+        client = self._require_client()
+        try:
+            client.activate_app(app_id)
+        except Exception as exc:
+            raise DriverError("app launch failed") from exc
+
+    def terminate(self, app_id: str) -> None:
+        client = self._require_client()
+        try:
+            client.terminate_app(app_id)
+        except Exception as exc:
+            raise DriverError("app terminate failed") from exc
+
+    def tree(self) -> str:
+        client = self._require_client()
+        try:
+            return client.page_source
+        except Exception as exc:
+            raise DriverError("ui tree retrieval failed") from exc
+
+    def home(self) -> None:
+        client = self._require_client()
+        try:
+            client.execute_script("mobile: pressKey", {"keycode": _KEYCODE_HOME})
+        except Exception as exc:
+            raise DriverError("home failed") from exc
+
+    def lock(self) -> None:
+        client = self._require_client()
+        try:
+            client.lock()
+        except Exception as exc:
+            raise DriverError("lock failed") from exc
+
+    def unlock(self) -> None:
+        client = self._require_client()
+        try:
+            client.unlock()
+        except Exception as exc:
+            raise DriverError("unlock failed") from exc
+
+    def _require_client(self) -> Any:
+        if self._client is None:
+            raise DeviceOfflineError("device offline")
+        return self._client
+
+
+def _drag_speed(
+    start_x: float,
+    start_y: float,
+    end_x: float,
+    end_y: float,
+    duration_ms: int,
+) -> int:
+    """Convert ``Driver.swipe``'s ``duration_ms`` into a drag speed (px/s).
+
+    ``mobile: dragGesture`` takes a speed in pixels/second rather than a
+    duration. Convert via ``distance / seconds`` and guard against a
+    zero/near-zero distance that would otherwise divide by zero.
+    """
+    distance = math.hypot(end_x - start_x, end_y - start_y)
+    seconds = duration_ms / 1000
+    if seconds <= 0:
+        return _DEFAULT_DRAG_SPEED_PX_PER_SEC
+    if distance < 1.0:
+        return _DEFAULT_DRAG_SPEED_PX_PER_SEC
+    return int(distance / seconds)