feat: add wUSDT bridge feature module

- Add feature-bridge-api module with domain models:
  - BridgeConfig: bridge configuration (addresses, fees, limits)
  - BridgeStatus: backing ratio, reserves, operational status
  - BridgeTransaction: deposit/withdrawal records

- Add feature-bridge-impl module with UI:
  - BridgeDepositFragment: shows Polkadot deposit address with QR code
  - BridgeStatusFragment: shows backing ratio and transparency info

Bridge enables 1:1 backed wUSDT on Pezkuwi Asset Hub,
backed by real USDT on Polkadot Asset Hub.

Bridge wallet: 16dSTc3BexjQKiPta7yNncF8nio4YgDQiPbudHzkuh7XJi8K (Polkadot)
wUSDT Asset ID: 1000, Min deposit: 10 USDT, Fee: 0.1%

feature-bridge-api/src/main/AndroidManifest.xml

@@ -0,0 +1,3 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+</manifest>

feature-bridge-api/src/main/java/io/novafoundation/nova/feature_bridge_api/di/BridgeFeatureApi.kt

@@ -0,0 +1,8 @@
+package io.novafoundation.nova.feature_bridge_api.di
+
+import io.novafoundation.nova.feature_bridge_api.domain.model.BridgeConfig
+
+interface BridgeFeatureApi {
+
+    val bridgeConfig: BridgeConfig
+}

feature-bridge-api/src/main/java/io/novafoundation/nova/feature_bridge_api/domain/model/BridgeConfig.kt

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+package io.novafoundation.nova.feature_bridge_api.domain.model
+
+import java.math.BigDecimal
+
+/**
+ * wUSDT Bridge Configuration
+ *
+ * This bridge enables 1:1 backed wUSDT on Pezkuwi Asset Hub,
+ * backed by real USDT on Polkadot Asset Hub.
+ */
+data class BridgeConfig(
+    /** Bridge wallet address on Polkadot Asset Hub (for deposits) */
+    val polkadotDepositAddress: String,
+
+    /** Bridge wallet address on Pezkuwi Asset Hub */
+    val pezkuwiAddress: String,
+
+    /** USDT Asset ID on Polkadot Asset Hub */
+    val polkadotUsdtAssetId: Int,
+
+    /** wUSDT Asset ID on Pezkuwi Asset Hub */
+    val pezkuwiWusdtAssetId: Int,
+
+    /** Minimum deposit amount in USDT */
+    val minDeposit: BigDecimal,
+
+    /** Minimum withdrawal amount in USDT */
+    val minWithdraw: BigDecimal,
+
+    /** Bridge fee in basis points (e.g., 10 = 0.1%) */
+    val feeBasisPoints: Int
+) {
+    companion object {
+        val DEFAULT = BridgeConfig(
+            polkadotDepositAddress = "16dSTc3BexjQKiPta7yNncF8nio4YgDQiPbudHzkuh7XJi8K",
+            pezkuwiAddress = "5Hh9KGn7oBTvtBPNcUvNeTQyw6oQrNfGdtsRU11QMc618Rse",
+            polkadotUsdtAssetId = 1984,
+            pezkuwiWusdtAssetId = 1000,
+            minDeposit = BigDecimal("10"),
+            minWithdraw = BigDecimal("10"),
+            feeBasisPoints = 10
+        )
+    }
+
+    /** Fee percentage as a human-readable string */
+    val feePercentage: String
+        get() = "${feeBasisPoints.toDouble() / 100}%"
+
+    /** Calculate fee for a given amount */
+    fun calculateFee(amount: BigDecimal): BigDecimal {
+        return amount.multiply(BigDecimal(feeBasisPoints)).divide(BigDecimal(10000))
+    }
+
+    /** Calculate net amount after fee */
+    fun calculateNetAmount(amount: BigDecimal): BigDecimal {
+        return amount.subtract(calculateFee(amount))
+    }
+}

feature-bridge-api/src/main/java/io/novafoundation/nova/feature_bridge_api/domain/model/BridgeStatus.kt

@@ -0,0 +1,37 @@
+package io.novafoundation.nova.feature_bridge_api.domain.model
+
+import java.math.BigDecimal
+
+/**
+ * Bridge status showing backing ratio and reserves
+ */
+data class BridgeStatus(
+    /** Total USDT held in bridge wallet on Polkadot */
+    val totalUsdtBacking: BigDecimal,
+
+    /** Total wUSDT in circulation on Pezkuwi */
+    val totalWusdtCirculating: BigDecimal,
+
+    /** Bridge operational status */
+    val isOperational: Boolean,
+
+    /** Last sync timestamp */
+    val lastSyncTimestamp: Long
+) {
+    /** Backing ratio (should be >= 100%) */
+    val backingRatio: BigDecimal
+        get() = if (totalWusdtCirculating > BigDecimal.ZERO) {
+            totalUsdtBacking.divide(totalWusdtCirculating, 4, java.math.RoundingMode.HALF_UP)
+                .multiply(BigDecimal(100))
+        } else {
+            BigDecimal(100)
+        }
+
+    /** Reserve (excess USDT in bridge, i.e., collected fees) */
+    val reserve: BigDecimal
+        get() = totalUsdtBacking.subtract(totalWusdtCirculating).coerceAtLeast(BigDecimal.ZERO)
+
+    /** Is the bridge fully backed? */
+    val isFullyBacked: Boolean
+        get() = backingRatio >= BigDecimal(100)
+}

feature-bridge-api/src/main/java/io/novafoundation/nova/feature_bridge_api/domain/model/BridgeTransaction.kt

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+package io.novafoundation.nova.feature_bridge_api.domain.model
+
+import java.math.BigDecimal
+
+enum class BridgeTransactionType {
+    DEPOSIT,    // Polkadot USDT -> Pezkuwi wUSDT
+    WITHDRAW    // Pezkuwi wUSDT -> Polkadot USDT
+}
+
+enum class BridgeTransactionStatus {
+    PENDING,
+    PROCESSING,
+    COMPLETED,
+    FAILED
+}
+
+/**
+ * A bridge transaction (deposit or withdrawal)
+ */
+data class BridgeTransaction(
+    val id: String,
+    val type: BridgeTransactionType,
+    val status: BridgeTransactionStatus,
+    val amount: BigDecimal,
+    val fee: BigDecimal,
+    val netAmount: BigDecimal,
+    val sourceAddress: String,
+    val destinationAddress: String,
+    val sourceTxHash: String?,
+    val destinationTxHash: String?,
+    val createdAt: Long,
+    val completedAt: Long?
+)

feature-bridge-api/src/main/java/io/novafoundation/nova/feature_bridge_api/presentation/BridgeRouter.kt

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+package io.novafoundation.nova.feature_bridge_api.presentation
+
+interface BridgeRouter {
+
+    fun openBridgeDeposit()
+
+    fun openBridgeWithdraw()
+
+    fun openBridgeStatus()
+
+    fun back()
+}