feat: Lighten MainApplication.onCreate for faster startup

- Moves non-critical initializations (ANR watchdog, worker scheduling) to background threads.
- Uses lazy initialization for the ANR watchdog to avoid upfront object creation.
- Moves theme configuration (which involves disk I/O) off the main thread.
- Adds `android.os.Trace` calls to `onCreate` for startup performance profiling.
- Moves API client initialization to a background thread.

Author: google-labs-jules[bot]

app/src/main/java/org/ole/planet/myplanet/MainApplication.kt

@@ -7,6 +7,7 @@ import android.content.Intent
 import android.content.SharedPreferences
 import android.content.res.Configuration
 import android.os.Bundle
+import android.os.Trace
 import android.os.StrictMode
 import android.os.StrictMode.VmPolicy
 import android.provider.Settings
@@ -176,24 +177,37 @@ class MainApplication : Application(), Application.ActivityLifecycleCallbacks {
     private var activityReferences = 0
     private var isActivityChangingConfigurations = false
     private var isFirstLaunch = true
-    private lateinit var anrWatchdog: ANRWatchdog
+    private var anrWatchdogStarted = false
+    private val anrWatchdog: ANRWatchdog by lazy {
+        ANRWatchdog(timeout = 5000L, listener = object : ANRWatchdog.ANRListener {
+            override fun onAppNotResponding(message: String, blockedThread: Thread, duration: Long) {
+                applicationScope.launch {
+                    createLog("anr", "ANR detected! Duration: ${duration}ms\n $message")
+                }
+            }
+        })
+    }
 
     override fun onCreate() {
         super.onCreate()
+        Trace.beginSection("MainApplication.onCreate")
         initApp()
         setupCriticalProperties()
-        ensureApiClientInitialized()
         setupStrictMode()
         registerExceptionHandler()
         setupLifecycleCallbacks()
         configureTheme()
 
         applicationScope.launch {
+            ensureApiClientInitialized()
             initializeDatabaseConnection()
+            observeNetworkForDownloads()
+        }
+        applicationScope.launch(Dispatchers.Default) {
             setupAnrWatchdog()
             scheduleWorkersOnStart()
-            observeNetworkForDownloads()
         }
+        Trace.endSection()
     }
 
     private fun initApp() {
@@ -239,14 +253,10 @@ class MainApplication : Application(), Application.ActivityLifecycleCallbacks {
 
     private suspend fun setupAnrWatchdog() {
         withContext(Dispatchers.Default) {
-            anrWatchdog = ANRWatchdog(timeout = 5000L, listener = object : ANRWatchdog.ANRListener {
-                override fun onAppNotResponding(message: String, blockedThread: Thread, duration: Long) {
-                    applicationScope.launch {
-                        createLog("anr", "ANR detected! Duration: ${duration}ms\n $message")
-                    }
-                }
-            })
-            anrWatchdog.start()
+            if (!anrWatchdogStarted) {
+                anrWatchdog.start()
+                anrWatchdogStarted = true
+            }
         }
     }
 
@@ -276,8 +286,12 @@ class MainApplication : Application(), Application.ActivityLifecycleCallbacks {
     }
 
     private fun configureTheme() {
-        val savedThemeMode = getCurrentThemeMode()
-        applyThemeMode(savedThemeMode)
+        applicationScope.launch(Dispatchers.IO) {
+            val savedThemeMode = getCurrentThemeMode()
+            withContext(Dispatchers.Main) {
+                applyThemeMode(savedThemeMode)
+            }
+        }
     }
 
     private suspend fun observeNetworkForDownloads() {
@@ -392,7 +406,7 @@ class MainApplication : Application(), Application.ActivityLifecycleCallbacks {
     }
 
     override fun onTerminate() {
-        if (::anrWatchdog.isInitialized) {
+        if (anrWatchdogStarted) {
             anrWatchdog.stop()
         }
         super.onTerminate()