fix: remove conflicting broad scheme from MainActivity to prevent Android disambiguation dialog

[subhankarmaiti]

Summary

• When customScheme in the Auth0 plugin config matches the app's Expo scheme (e.g., both set to "smtest"), Android shows a chooser dialog during the Auth0 login callback because both MainActivity (broad scheme handler added by @expo/config-plugins) and RedirectActivity (specific Auth0 callback handler) are registered for the same URL scheme
• The Expo plugin (addAndroidAuth0Manifest) now removes conflicting broad scheme data elements (same scheme, no android:host) from other activities before adding the Auth0-specific intent filter to RedirectActivity, mirroring the existing iOS deduplication logic in addIOSAuth0ConfigInInfoPList
• Only broad matchers are removed — data elements with an android:host are preserved since they won't cause disambiguation

Root Cause

Expo's @expo/config-plugins adds <data android:scheme="smtest"/> to MainActivity for deep linking. The react-native-auth0 plugin then adds <data android:scheme="smtest" android:host="..." android:pathPrefix="..."/> to RedirectActivity. When Chrome Custom Tab redirects back after authentication, it finds two exported activities matching the scheme and shows a disambiguation dialog. iOS already handles this via dedup in addIOSAuth0ConfigInInfoPList. Android was missing the equivalent.

Test plan

• Added test: conflicting broad scheme is removed from MainActivity
• Added test: non-conflicting schemes on other activities are left untouched
• Added test: scheme data with android:host (specific match) is preserved
• Verify Auth0 login flow completes without disambiguation dialog on Android
• Verify exp+<scheme> deep links still work in dev mode
• Verify existing snapshot tests still pass