Complete Pezkuwi rebrand for Play Store release

User-visible changes:
- All strings.xml: Nova → Pezkuwi (12 languages, 721 references)
- App name: Pezkuwi Wallet
- Deep links: pezkuwiwallet://
- WalletConnect: Pezkuwi Wallet metadata
- Backup files: pezkuwiwallet_backup.json
- Push notifications: Pezkuwi Wallet branding

Technical changes:
- Gradle namespaces: io.pezkuwichain.wallet.*
- JS interface prefix: Pezkuwi_*
- User-Agent: Pezkuwi Wallet (Android)
- Firebase: pezkuwi-wallet project config

Assets:
- Nevroz fire logo (Kurdish colors theme)
- 6 density PNG files

Documentation:
- PACKAGE_STRUCTURE_REBRAND.md for future refactoring

feature-cloud-backup-impl/src/main/java/io/novafoundation/nova/feature_cloud_backup_impl/data/cloudStorage/GoogleDriveBackupStorage.kt

@@ -203,7 +203,7 @@ internal class GoogleDriveBackupStorage(
         credential.selectedAccount = account!!.account
 
         return Drive.Builder(NetHttpTransport(), GsonFactory(), credential)
-            .setApplicationName("Nova Wallet")
+            .setApplicationName("Pezkuwi Wallet")
             .build()
     }
 
@@ -211,9 +211,9 @@ internal class GoogleDriveBackupStorage(
 
     private fun backupFileName(): String {
         return if (debug) {
-            "novawallet_backup_debug.json"
+            "pezkuwiwallet_backup_debug.json"
         } else {
-            "novawallet_backup.json"
+            "pezkuwiwallet_backup.json"
         }
     }
 }