Mobile Attribution Setup: Branch to RevenueCat

We need to validate our attribution pipeline on iOS and Android to get Branch attribution data flowing correctly into RevenueCat so we can accurately connect installs and campaigns to subscription revenue. 1. Implement the Branch initSession callback on iOS and Android to capture attribution data 2. Pass Branch attribution (channel, campaign, ad group, etc.) to RevenueCat as subscriber attributes 3. Validate the data appears correctly in RevenueCat customer profiles 4. Set up Branch to forward attribution data to GA4 via Firebase on both platforms 5. Map Branch parameters to the appropriate GA4 event properties 6. Validate events and attribution appear correctly in GA4 reports 7. test Branch links and walk through the full attribution flow end-to-end 8. Confirm data appears correctly in both RevenueCat and GA4 9. Provide a short summary doc of what was implemented and how to verify it going forward