fix: revert gradle namespaces, add release Firebase config

Reverted gradle namespace changes (io.pezkuwichain.wallet -> io.novafoundation.nova)
because they break R class references in Kotlin code.

Internal namespaces are NOT user-visible, so this is acceptable for minimum rebrand.
User-visible elements are all properly branded as Pezkuwi.

Added google-services.json for release variant.

feature-dapp-impl/build.gradle

@@ -19,7 +19,7 @@ android {
             buildConfigField "String", "DAPP_METADATAS_URL", "\"https://raw.githubusercontent.com/pezkuwichain/pezkuwi-wallet-utils/master/dapps/dapps_full.json\""
         }
     }
-    namespace 'io.pezkuwichain.wallet.feature_dapp_impl'
+    namespace 'io.novafoundation.nova.feature_dapp_impl'
 
     packagingOptions {
         resources.excludes.add("META-INF/NOTICE.md")