feat: implement first run tracking; update PreferencesManager to manage first run state and integrate with MainApp

CollabTableAndroid/app/src/main/java/com/collabtable/app/data/preferences/PreferencesManager.kt

@@ -16,6 +16,9 @@ class PreferencesManager(
     private val _serverUrl = MutableStateFlow(getServerUrl())
     val serverUrl: StateFlow<String> = _serverUrl.asStateFlow()
 
+    private val _isFirstRun = MutableStateFlow(isFirstRun())
+    val isFirstRunFlow: StateFlow<Boolean> = _isFirstRun.asStateFlow()
+
     private val _themeMode = MutableStateFlow(getThemeMode())
     val themeMode: StateFlow<String> = _themeMode.asStateFlow()
 
@@ -64,6 +67,7 @@ class PreferencesManager(
 
     fun setIsFirstRun(isFirstRun: Boolean) {
         prefs.edit().putBoolean(KEY_FIRST_RUN, isFirstRun).apply()
+        _isFirstRun.value = isFirstRun
     }
 
     fun getServerPassword(): String? = prefs.getString(KEY_SERVER_PASSWORD, null)

CollabTableAndroid/app/src/main/java/com/collabtable/app/ui/navigation/MainApp.kt

@@ -16,6 +16,7 @@ import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
@@ -47,9 +48,10 @@ private object Routes {
 fun MainApp() {
     val context = LocalContext.current
     val prefs = remember { PreferencesManager.getInstance(context) }
+    val isFirstRun by prefs.isFirstRunFlow.collectAsState()
 
     // Show setup flow until completed; then show main app with bottom nav
-    if (prefs.isFirstRun()) {
+    if (isFirstRun) {
         val navController = rememberNavController()
         NavHost(navController, startDestination = Routes.SETUP) {
             composable(Routes.SETUP) {