fix(test): Use Process.killProcess instead of am force-stop to preserve notifications

am force-stop (used by Maestro's killApp) clears all notifications on
API 33+, causing Test 4 (COLD start via notification) to always fail.

Adds a "Kill Process" button that calls Process.killProcess() which
kills the app process without clearing notifications. The Maestro test
now taps this button instead of using killApp.

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

Author: romtsn

sentry-android-integration-tests/sentry-uitest-android-critical/maestro/appStart.yaml

@@ -65,9 +65,9 @@ name: App Start Tests
       visible: "Allow"
     commands:
       - tapOn: "Allow"
-- tapOn: "Finish Activity"
-- assertNotVisible: "Welcome!"
-- killApp
+# Use "Kill Process" button instead of killApp to avoid am force-stop
+# which clears notifications on API 33+
+- tapOn: "Kill Process"
 - waitForAnimationToEnd
 - repeat:
     times: 5

sentry-android-integration-tests/sentry-uitest-android-critical/src/main/java/io/sentry/uitest/android/critical/MainActivity.kt

@@ -99,6 +99,11 @@ class MainActivity : ComponentActivity() {
             ) {
               Text("Trigger Notification")
             }
+            Button(
+              onClick = { android.os.Process.killProcess(android.os.Process.myPid()) }
+            ) {
+              Text("Kill Process")
+            }
             Button(
               onClick = {
                 startActivity(