feat: implement device verification flow with new UI components and protocol handling

app/src/main/java/com/rosetta/messenger/database/SyncEntities.kt

@@ -0,0 +1,24 @@
+package com.rosetta.messenger.database
+
+import androidx.room.ColumnInfo
+import androidx.room.Dao
+import androidx.room.Entity
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.PrimaryKey
+import androidx.room.Query
+
+@Entity(tableName = "accounts_sync_times")
+data class AccountSyncTimeEntity(
+    @PrimaryKey @ColumnInfo(name = "account") val account: String,
+    @ColumnInfo(name = "last_sync") val lastSync: Long
+)
+
+@Dao
+interface SyncTimeDao {
+    @Query("SELECT last_sync FROM accounts_sync_times WHERE account = :account LIMIT 1")
+    suspend fun getLastSync(account: String): Long?
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun upsert(entity: AccountSyncTimeEntity)
+}