style: 代码清理 — 移除未使用的 import 和变量

- Platform.android.kt: 移除未使用的 kotlinx.coroutines.launch import
  和未使用的 scope 变量
- CalendarMonthView.kt: 移除未使用的 density 变量
- App.kt: 格式化缩进

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

shared/src/androidMain/kotlin/plus/rua/project/Platform.android.kt

@@ -4,7 +4,6 @@ import android.os.Build
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.rememberCoroutineScope
 import kotlinx.coroutines.CancellationException
-import kotlinx.coroutines.launch
 
 class AndroidPlatform : Platform {
     override val name: String = "Android ${Build.VERSION.SDK_INT}"
@@ -24,7 +23,7 @@ actual fun PredictiveBackHandler(
     onCancel: () -> Unit
 ) {
     if (Build.VERSION.SDK_INT >= 34) {
-        val scope = rememberCoroutineScope()
+        rememberCoroutineScope()
         androidx.activity.compose.PredictiveBackHandler(enabled) { progress ->
             try {
                 progress.collect { backEvent ->

shared/src/commonMain/kotlin/plus/rua/project/App.kt

@@ -57,11 +57,17 @@ fun App() {
                 if (targetState.ordinal > initialState.ordinal) {
                     // 正向导航：新页面从右侧滑入覆盖，旧页面略微左移+淡出
                     (slideInHorizontally { it } + fadeIn()) togetherWith
-                        (slideOutHorizontally { -it / 4 } + fadeOut())
+                            (slideOutHorizontally { -it / 4 } + fadeOut())
                 } else {
                     // 返回导航：新页面从左侧滑入，旧页面向右侧滑出
-                    (slideInHorizontally(animationSpec = tween(250)) { -it } + fadeIn(animationSpec = tween(250))) togetherWith
-                        (slideOutHorizontally(animationSpec = tween(250)) { it } + fadeOut(animationSpec = tween(250)))
+                    (slideInHorizontally(animationSpec = tween(250)) { -it } + fadeIn(
+                        animationSpec = tween(
+                            250
+                        )
+                    )) togetherWith
+                            (slideOutHorizontally(animationSpec = tween(250)) { it } + fadeOut(
+                                animationSpec = tween(250)
+                            ))
                 }
             },
             modifier = Modifier.fillMaxSize()
@@ -71,6 +77,7 @@ fun App() {
                     modifier = Modifier,
                     onNavigateToAbout = { currentScreen = Screen.About }
                 )
+
                 Screen.About -> {
                     PredictiveBackHandler(
                         enabled = backProgress == 0f,
@@ -88,6 +95,7 @@ fun App() {
                         }
                     )
                 }
+
                 Screen.Licenses -> {
                     PredictiveBackHandler(
                         enabled = backProgress == 0f,

shared/src/commonMain/kotlin/plus/rua/project/ui/CalendarMonthView.kt

@@ -89,7 +89,7 @@ fun CalendarMonthView(
 
     @Suppress("DEPRECATION") // monthNumber 无替代 API，kotlinx-datetime 尚未提供新接口
     val currentMonth by remember { derivedStateOf { viewModel.selectedDate.month.number } }
-    val density = LocalDensity.current
+    LocalDensity.current
 
     var rowHeightPx by remember { mutableIntStateOf(0) }
     var screenWidthPx by remember { mutableIntStateOf(0) }
@@ -448,6 +448,7 @@ private fun CalendarPagerArea(
                             weekMonday
                         }
                     }
+
                     else -> weekMonday
                 }
                 viewModel.selectDate(date)