fix(settings): write the no-dictionaries seed only after a completed scan

A racing SettingsViewModel whose scan short-circuits with an in-progress
error persisted hadNoDictionaries from a still-empty list, forcing the
Settings screen on the next cold start despite existing dictionaries.

app/src/main/java/com/example/research/ui/settings/SettingsViewModel.kt

@@ -274,9 +274,10 @@ class SettingsViewModel(
     }
 
     private fun initialize() {
+        var scanCompleted = false
         viewModelScope.launch {
             try {
-                scanDirectoryInternal(preferencesManager.dictionaryPath)
+                scanCompleted = scanDirectoryInternal(preferencesManager.dictionaryPath) is OperationResult.Success
             } catch (e: Exception) {
                 android.util.Log.e("SettingsViewModel", "Initial scan failed", e)
                 dictionaryStatus.value = if (localDictionaryRepository.dictionaries.value.isEmpty()) {
@@ -299,9 +300,11 @@ class SettingsViewModel(
                 }
                 hasLoadedPreferences.value = true
                 hasCompletedStartupScan.value = true
-                preferencesManager.setHadNoDictionaries(
-                    localDictionaryRepository.dictionaries.value.isEmpty()
-                )
+                if (scanCompleted) {
+                    preferencesManager.setHadNoDictionaries(
+                        localDictionaryRepository.dictionaries.value.isEmpty()
+                    )
+                }
             }
         }
     }