refactor: drop two over-engineered seams (enum + stdlib Base64) (#5945)

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

core/common/src/commonMain/kotlin/org/meshtastic/core/common/util/Base64Factory.kt

@@ -1,28 +0,0 @@
-/*
- * Copyright (c) 2026 Meshtastic LLC
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
-package org.meshtastic.core.common.util
-
-import kotlin.io.encoding.Base64
-import kotlin.io.encoding.ExperimentalEncodingApi
-
-/** Pure Kotlin Base64 utility — no expect/actual needed. */
-@OptIn(ExperimentalEncodingApi::class)
-object Base64Factory {
-    fun encode(data: ByteArray): String = Base64.Default.encode(data)
-
-    fun decode(data: String): ByteArray = Base64.Default.decode(data)
-}

core/ui/src/commonMain/kotlin/org/meshtastic/core/ui/component/ScrollToTopEvent.kt

@@ -24,10 +24,9 @@ import kotlinx.coroutines.flow.MutableSharedFlow
  * Event emitted when a user re-presses a bottom navigation destination that should trigger a scroll-to-top behaviour on
  * the corresponding screen.
  */
-sealed class ScrollToTopEvent {
-    data object NodesTabPressed : ScrollToTopEvent()
-
-    data object ConversationsTabPressed : ScrollToTopEvent()
+enum class ScrollToTopEvent {
+    NodesTabPressed,
+    ConversationsTabPressed,
 }
 
 @Composable fun rememberScrollToTopEvents(): MutableSharedFlow<ScrollToTopEvent> = remember { MutableSharedFlow() }

feature/messaging/src/commonMain/kotlin/org/meshtastic/feature/messaging/ui/contact/Contacts.kt

@@ -173,7 +173,7 @@ fun ContactsScreen(
 
     LaunchedEffect(scrollToTopEvents) {
         scrollToTopEvents?.collectLatest { event ->
-            if (event is ScrollToTopEvent.ConversationsTabPressed) {
+            if (event == ScrollToTopEvent.ConversationsTabPressed) {
                 contactsListState.smartScrollToTop(coroutineScope)
             }
         }

feature/node/src/commonMain/kotlin/org/meshtastic/feature/node/component/NodeDetailsSection.kt

@@ -49,7 +49,6 @@ import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.unit.dp
 import kotlinx.coroutines.launch
 import org.jetbrains.compose.resources.stringResource
-import org.meshtastic.core.common.util.Base64Factory
 import org.meshtastic.core.common.util.MetricFormatter
 import org.meshtastic.core.model.DeviceHardware
 import org.meshtastic.core.model.Node
@@ -92,6 +91,8 @@ import org.meshtastic.core.ui.icon.Verified
 import org.meshtastic.core.ui.icon.role
 import org.meshtastic.core.ui.util.createClipEntry
 import org.meshtastic.core.ui.util.formatAgo
+import kotlin.io.encoding.Base64
+import kotlin.io.encoding.ExperimentalEncodingApi
 
 @Composable
 fun NodeDetailsSection(
@@ -324,7 +325,7 @@ private fun MqttAndVerificationRow(node: Node) {
     }
 }
 
-@OptIn(ExperimentalFoundationApi::class)
+@OptIn(ExperimentalFoundationApi::class, ExperimentalEncodingApi::class)
 @Suppress("LongMethod", "MagicNumber")
 @Composable
 private fun PublicKeyItem(publicKeyBytes: ByteArray) {
@@ -335,7 +336,7 @@ private fun PublicKeyItem(publicKeyBytes: ByteArray) {
         if (isMismatch) {
             stringResource(Res.string.error)
         } else {
-            Base64Factory.encode(publicKeyBytes).trim()
+            Base64.Default.encode(publicKeyBytes).trim()
         }
     val label = stringResource(Res.string.public_key)
     val copyLabel = stringResource(Res.string.copy)

feature/node/src/commonMain/kotlin/org/meshtastic/feature/node/list/NodeListScreen.kt

@@ -114,7 +114,7 @@ fun NodeListScreen(
 
     LaunchedEffect(scrollToTopEvents) {
         scrollToTopEvents?.collectLatest { event ->
-            if (event is ScrollToTopEvent.NodesTabPressed) {
+            if (event == ScrollToTopEvent.NodesTabPressed) {
                 listState.smartScrollToTop(coroutineScope)
             }
         }