chore: 更新MainActivity与AndroidManifest

- 更新MainActivity.kt
- 更新AndroidManifest.xml

Co-authored-by: Cursor <cursoragent@cursor.com>

app-android/app/src/main/AndroidManifest.xml

@@ -26,7 +26,7 @@
             android:exported="true"
             android:label="@string/app_name"
             android:theme="@style/Theme.Lifeecho"
-            android:windowSoftInputMode="adjustResize" >
+            android:windowSoftInputMode="adjustPan" >
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 

app-android/app/src/main/java/com/huaga/life_echo/MainActivity.kt

@@ -229,7 +229,11 @@ fun LifeechoApp(initialLoggedIn: Boolean = false) {
             }
         }
     ) { paddingValues ->
-        Box(modifier = Modifier.padding(paddingValues)) {
+        Box(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues)
+        ) {
             AppNavigation(
                 navController = navController,
                 isLoggedIn = isLoggedIn,