feat: merge rustore test UI and unify SKU format across channels

- Merge VK login/link/check and Review test buttons from dev_rustore
- Unify Rustore/GooglePlay SKU format via ChannelHelpers.normalizeSkuList()
- Fix ChannelConfig runtime sync: Java InitSDK sets channel from ChannelHelpers.CHANNEL
- Fix AndroidMinSdkVersion 25→26 for tuyoosdk compatibility
- Fix Flexion AndroidManifest tools:replace missing fullBackupContent value
- Add [CHANNEL-VERIFY] debug logs for channel verification

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

sdk-intergration/Assets/Plugins/Android/settingsTemplate.gradle

@@ -18,6 +18,9 @@ dependencyResolutionManagement {
         mavenCentral()
 // Android Resolver Repos Start
         def unityProjectPath = $/file:///**DIR_UNITYPROJECT**/$.replace("\\", "/")
+        maven {
+            url "https://sdk.tapjoy.com/" // Packages/com.unity.package-offerwall/Editor/TJPluginDependencies.xml:9
+        }
         maven {
             url "https://android-sdk.is.com/" // Assets/MaxSdk/Mediation/IronSource/Editor/Dependencies.xml:8
         }