feat: migrate secret management to datastore proto and tink

app/src/main/java/com/bitcointxoko/gudariwallet/service/WalletNotificationService.kt

@@ -118,7 +118,7 @@ class WalletNotificationService : Service() {
 
         // Step 2: Open the WebSocket. If already open (e.g. service restarted
         // by Android after a kill), close the old one first.
-        openWebSocket()
+        serviceScope.launch { openWebSocket() }
 
         // START_REDELIVER_INTENT: if Android kills the service under memory
         // pressure, it will restart it and re-deliver the last intent.
@@ -141,19 +141,21 @@ class WalletNotificationService : Service() {
 
     // ── WebSocket ─────────────────────────────────────────────────────────────
 
-    private fun openWebSocket() {
+    private suspend fun openWebSocket() {
         val secrets = EncryptedSecretStore(applicationContext)
+        val invoiceKey = secrets.invoiceKey()
+        val baseUrl    = secrets.baseUrl()
 
-        if (secrets.invoiceKey.isBlank() || secrets.baseUrl.isBlank()) {
+        if (invoiceKey.isBlank() || baseUrl.isBlank()) {
             Log.e(TAG, "Credentials not available — cannot open WebSocket")
             stopSelf()
             return
         }
 
-        val wsUrl = secrets.baseUrl
+        val wsUrl = baseUrl
             .replace("https://", "wss://")
             .replace("http://", "ws://")
-            .trimEnd('/') + "/api/v1/ws/${secrets.invoiceKey}"
+            .trimEnd('/') + "/api/v1/ws/${invoiceKey}"
 
         Log.d(TAG, "Opening WebSocket: $wsUrl")