Callback multi invoke fix + SDK updates

[al-af]

Core Fixes

Android: CallbackGuard

• Added CallbackGuard class to prevent double callback invocation (thread-safe, leak-safe)
• Applied to all 20+ @ReactMethod callbacks in RNAppsFlyerModule.java
• Impact: Fixes crashes in React Native New Architecture

Expo Android: Backup Rules (Issue #631)

• Removed hardcoded expo-secure-store XML references
• Added preferAppsFlyerBackupRules opt-in flag
• Default: no longer modifies app's backup rules
• Impact: Fixes Expo Android build failures when expo-secure-store is absent

iOS: Swift Header Import (PR #653)

• Added fallback import mechanism in PCAppsFlyer.m for different CocoaPods configurations
• Impact: Fixes build issues across CocoaPods setups

Version Updates

• Android SDK: 6.17.3 → 6.17.5
• iOS SDK: 6.17.7 → 6.17.8 (Framework, Strict, PurchaseConnector)
• Plugin: 6.17.7 → 6.17.8

API Changes

validateAndLogInAppPurchase

• v1: Marked @deprecated
• v2: Promoted to stable (removed "Beta"), docs updated with iOS error handling examples

TypeScript (index.d.ts)

• Fixed import paths for Purchase Connector models
• Fixed type names: onFailure → OnFailure
• Updated additionalParameters type, StoreKitVersion readonly, AppsFlyerConsent types

Testing & Tooling

• New: compatibility.test.js - backward compatibility tests
• New: linting.test.js - ESLint validation tests
• Updated: index.test.js - uncommented validateAndLogInAppPurchaseV2 tests
• Updated: jest.config.js - includes all .test.js files
• New: .eslintrc.js + lint scripts in package.json

Documentation

• RN_API.md: Updated consent flow, v2 purchase API, deprecation notices
• RN_ExpoInstallation.md: Added preferAppsFlyerBackupRules documentation
• RN_InAppEvents.md: Added v1 API deprecation notice
• RN_EspIntegration.md: Updated backup rules references

Cleanup

• Removed ios/AppsFlyerLib-Swift.h (its auto-generated)

[amit-kremer93]

Looks good. 2 general notes but in general looks good