chore: Release 6.1.9

[onesignal-deploy]

Channels: Current

🛠️ Native Dependency Updates

• Update Android SDK from 5.9.2 to 5.9.3
  • fix: [SDK-4732] track activity lifecycle from process start to fix late-init focus (#2655)
  • fix: [SDK-4735] route requestPermission fallbackToSettings to settings when permanently denied (#2656)
• Update iOS SDK from 5.5.1 to 5.5.2
  • fix: Preserve user identity across iOS prewarm launches (OneSignal-iOS-SDK#1669)
  • internal refactor: route identifier reads through OneSignalIdentifiers (OneSignal-iOS-SDK#1667)

[claude]

LGTM, straightforward release bump.

Extended reasoning...

Overview

This PR bumps the .NET SDK from 6.1.8 to 6.1.9, updating the bundled Android SDK from 5.9.2 to 5.9.3. The diff consists of three replaced AAR binaries (core, location, notifications), a version string change in OneSignalSDK.DotNet.nuspec, and a version update in versions.json. No source code changes are involved.

Security risks

None apparent in the wrapper changes. Security depends on the upstream Android SDK release notes, which describe two fixes: activity lifecycle tracking (SDK-4732) and routing requestPermission fallbackToSettings appropriately (SDK-4735). Neither is described as a security fix; both are behavioral bug fixes.

Level of scrutiny

Low. This is a mechanical release PR following the established pattern in this repo (cf. the prior 6.1.8 release PR #180). The text changes are trivial version bumps, and the binary changes correspond to an upstream patch release.

Other factors

No bugs were found by the bug hunting system. There are no outstanding reviewer comments. The change follows the project'''s standard release flow.