sdk bump to 8.8.0

[nw-sentry]

Upgrades the Sentry RN SDK to v8, which pulls in Cocoa SDK v9 and Sentry Android Gradle Plugin v6. Per the v7 → v8 migration guide, this requires matching bumps to our iOS deployment target and Android build tooling.

Changes

• ios/Podfile.lock — Regenerated. RNSentry 7.8.0 → 8.8.0, and Sentry/HybridSDK 8.57.3 → Sentry 9.10.0 per the Cocoa v9 upgrade.
• ios/sentry_react_native.xcodeproj/project.pbxproj — IPHONEOS_DEPLOYMENT_TARGET 13.4 → 15.1 (app + test targets, Debug + Release). Required by the new iOS 15.0+ minimum.
• android/build.gradle — sentry-android-gradle-plugin 3.12.0 → 6.0.0, required by v8 (Android section).
• src/screens/EndToEndTestsScreen.tsx — beforeSend param typed as Sentry.ErrorEvent instead of Sentry.Event to match the v8 type signature.
• package-lock.json — Regenerated for the new dependency tree.
• Bumped iOS CI runner from macos-14 to macos-15 so builds use Xcode 16.4 (the macos-15 default). This fixes the module '_SentryPrivate' not found failure

Test plan

• iOS build succeeds in Xcode 16.4+ targeting iOS 15.1+
• Android build succeeds with Sentry AGP 6.0.0
• JS error, native iOS crash, and native Android crash all reach Sentry

[antonis]

LGTM 🚀