feat(splash): add SplashActivity with 400ms delay

app/src/main/kotlin/plus/rua/project/SplashActivity.kt

@@ -0,0 +1,45 @@
+package plus.rua.project
+
+import android.content.Intent
+import android.os.Bundle
+import androidx.activity.compose.setContent
+import androidx.compose.ui.res.painterResource
+import androidx.lifecycle.lifecycleScope
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+import plus.rua.project.shared.R as CoreR
+import plus.rua.project.ui.SplashScreen
+import plus.rua.project.ui.theme.YaYaTheme
+
+private const val SPLASH_DELAY_MS = 400L
+
+/**
+ * 启动页 Activity。
+ *
+ * 显示品牌启动图 400ms 后跳转到 [MainActivity]，并 finish 自身。
+ */
+class SplashActivity : BaseActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        setContent {
+            YaYaTheme {
+                SplashScreen(
+                    backgroundPainter = painterResource(CoreR.drawable.launch_bg),
+                    iconPainter = painterResource(R.mipmap.ic_launcher),
+                )
+            }
+        }
+
+        lifecycleScope.launch {
+            delay(SPLASH_DELAY_MS)
+            navigateToMain()
+        }
+    }
+
+    private fun navigateToMain() {
+        if (isFinishing) return
+        startActivityWithSlide(Intent(this, MainActivity::class.java))
+        finish()
+    }
+}