refactor(e2e): Consolidate Android build scripts per review feedback

Replaces separate build-android-debug-auto.sh and build-android-debug-manual.sh
scripts with a single consolidated build-android-debug-init.sh that validates
SENTRY_DISABLE_NATIVE_START and provides clear error messages.

Key improvements:
- Single source of truth for Android build logic
- Environment variable validation with helpful error messages
- Maps true/false to auto/manual build modes
- Dynamic APK naming based on mode
- Error handling if APK not found

Package.json now calls the script directly with the env var inline,
eliminating the need for wrapper scripts while maintaining the same
developer ergonomics (yarn build-android-debug-auto/manual still work).

Addresses review feedback from lucas-zimerman at:
#5583 (comment)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: antonis

samples/react-native/package.json

@@ -10,8 +10,8 @@
     "build-android-release-legacy": "scripts/build-android-release-legacy.sh",
     "build-android-debug": "scripts/build-android-debug.sh",
     "build-android-debug-legacy": "scripts/build-android-debug-legacy.sh",
-    "build-android-debug-auto": "scripts/build-android-debug-auto.sh",
-    "build-android-debug-manual": "scripts/build-android-debug-manual.sh",
+    "build-android-debug-auto": "SENTRY_DISABLE_NATIVE_START=true scripts/build-android-debug-init.sh",
+    "build-android-debug-manual": "SENTRY_DISABLE_NATIVE_START=false scripts/build-android-debug-init.sh",
     "build-ios-release": "scripts/build-ios-release.sh",
     "build-ios-debug": "scripts/build-ios-debug.sh",
     "test": "jest",

samples/react-native/scripts/build-android-debug-auto.sh

@@ -0,0 +1,47 @@
+#!/bin/bash
+
+# Exit on error
+set -e
+
+thisFilePath=$(dirname "$0")
+
+# Validate SENTRY_DISABLE_NATIVE_START is set
+if [ -z "${SENTRY_DISABLE_NATIVE_START}" ]; then
+  echo "Error: SENTRY_DISABLE_NATIVE_START environment variable is not set."
+  echo "Usage: SENTRY_DISABLE_NATIVE_START=true|false $0"
+  echo ""
+  echo "  true  - Build for auto init from JS (native SDK disabled)"
+  echo "  false - Build for manual native init (native SDK enabled)"
+  exit 1
+fi
+
+# Map SENTRY_DISABLE_NATIVE_START to build mode
+if [ "${SENTRY_DISABLE_NATIVE_START}" = "true" ]; then
+  BUILD_MODE="auto"
+  INIT_DESCRIPTION="initialize Sentry from JavaScript (auto init)"
+elif [ "${SENTRY_DISABLE_NATIVE_START}" = "false" ]; then
+  BUILD_MODE="manual"
+  INIT_DESCRIPTION="initialize Sentry natively before JS (manual init)"
+else
+  echo "Error: Invalid value for SENTRY_DISABLE_NATIVE_START: '${SENTRY_DISABLE_NATIVE_START}'"
+  echo "Expected 'true' or 'false'"
+  exit 1
+fi
+
+export RN_ARCHITECTURE="new"
+export CONFIG="debug"
+
+echo "Building Android with SENTRY_DISABLE_NATIVE_START=${SENTRY_DISABLE_NATIVE_START}"
+echo "This build will ${INIT_DESCRIPTION}"
+
+"${thisFilePath}/build-android.sh"
+
+# Rename the output APK based on build mode
+cd "${thisFilePath}/.."
+if [ -f "app.apk" ]; then
+  mv app.apk "app-${BUILD_MODE}.apk"
+  echo "Build complete: app-${BUILD_MODE}.apk"
+else
+  echo "Error: Expected output file 'app.apk' not found"
+  exit 1
+fi