Android: StrictMode (debug) + off-main-thread IO — root resolver, file import, and DateFormat moved off composition/main; details label preformatted

android/app/src/main/java/com/shonar/ShonarApplication.kt

@@ -51,6 +51,15 @@ class ShonarApplication : Application() {
 
     override fun onCreate() {
         super.onCreate()
+        if (android.os.Build.VERSION.SDK_INT >= 9 && runCatching {
+            (applicationInfo.flags and android.content.pm.ApplicationInfo.FLAG_DEBUGGABLE) != 0
+        }.getOrDefault(false)) {
+            android.os.StrictMode.setThreadPolicy(
+                android.os.StrictMode.ThreadPolicy.Builder()
+                    .detectDiskReads().detectDiskWrites().detectNetwork()
+                    .detectCustomSlowCalls().penaltyLog().build()
+            )
+        }
         appScope.launch {
             runCatching { recordingRepository.refreshRoot() }
         }

android/app/src/main/java/com/shonar/recording/RecordingRepository.kt

@@ -1,9 +1,11 @@
 package com.shonar.recording
 
 import com.shonar.provider.SyncState
+import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
+import kotlinx.coroutines.withContext
 import java.io.File
 import java.text.DateFormat
 import java.util.Date
@@ -36,7 +38,9 @@ class RecordingRepository(
 
     /** Re-read the destination (call at startup and after a location change). */
     suspend fun refreshRoot() {
-        libraryRoot = runCatching { rootResolver?.invoke() }.getOrNull() ?: legacyDir
+        libraryRoot = withContext(Dispatchers.IO) {
+            runCatching { rootResolver?.invoke() }.getOrNull() ?: legacyDir
+        }
         libraryRoot.mkdirs()
         importExistingFiles()
     }
@@ -53,6 +57,10 @@ class RecordingRepository(
      * never create duplicate rows.
      */
     suspend fun importExistingFiles() = importMutex.withLock {
+        withContext(Dispatchers.IO) { importExistingFilesLocked() }
+    }
+
+    private suspend fun importExistingFilesLocked() {
         val root = libraryRoot
         val known = dao.getAll().mapNotNullTo(mutableSetOf()) {
             runCatching { File(it.filePath).canonicalPath }.getOrNull()

android/app/src/main/java/com/shonar/ui/detail/DetailsScreen.kt

@@ -35,8 +35,6 @@ import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.shonar.ShonarApplication
-import java.text.DateFormat
-import java.util.Date
 
 /**
  * Recording details: playback, rename, file info. Local-only — no tabs,
@@ -170,8 +168,7 @@ private fun InfoCard(ready: DetailsViewModel.Ready) {
         Column(Modifier.padding(16.dp), verticalArrangement = Arrangement.spacedBy(4.dp)) {
             InfoRow("Length", formatMs(r.durationMs))
             InfoRow("Size", formatBytes(r.sizeBytes))
-            InfoRow("Recorded", DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.SHORT)
-                .format(Date(r.createdAtEpochMs)))
+            InfoRow("Recorded", ready.recordedLabel)
             InfoRow("File", r.filePath.substringAfterLast('/'))
         }
     }

android/app/src/main/java/com/shonar/ui/detail/DetailsViewModel.kt

@@ -31,6 +31,8 @@ class DetailsViewModel(
         val speed: Float = 1f,
         val playbackError: String? = null,
         val saveError: String? = null,
+        /** Pre-formatted off the UI thread: DateFormat hits disk on first use. */
+        val recordedLabel: String = "",
     )
 
     sealed interface UiState {
@@ -56,6 +58,14 @@ class DetailsViewModel(
                 override fun <T : ViewModel> create(modelClass: Class<T>): T =
                     DetailsViewModel(app, recordingId) as T
             }
+
+        /** DateFormat loads locale/tz data from disk — never call in composition. */
+        suspend fun formatRecorded(epochMs: Long): String =
+            kotlinx.coroutines.withContext(kotlinx.coroutines.Dispatchers.IO) {
+                java.text.DateFormat
+                    .getDateTimeInstance(java.text.DateFormat.MEDIUM, java.text.DateFormat.SHORT)
+                    .format(java.util.Date(epochMs))
+            }
     }
 
     init {
@@ -70,7 +80,13 @@ class DetailsViewModel(
                 _state.value = UiState.Error("Recording not found.")
                 return@launch
             }
-            _state.value = UiState.ReadyState(Ready(recording = entity, durationMs = entity.durationMs))
+            _state.value = UiState.ReadyState(
+                Ready(
+                    recording = entity,
+                    durationMs = entity.durationMs,
+                    recordedLabel = formatRecorded(entity.createdAtEpochMs),
+                )
+            )
         }
     }