build: 启用 R8 压缩与资源优化，添加 ProGuard 规则

- androidApp: 启用 isMinifyEnabled 和 isShrinkResources
- androidApp: ABI 过滤（arm64-v8a, armeabi-v7a），关闭 buildConfig
- gradle.properties: 启用并行构建、守护进程、R8 fullMode
- 新建 proguard-rules.pro 保留 KMP/Compose/kotlinx.datetime 规则

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

androidApp/build.gradle.kts

@@ -14,7 +14,28 @@ android {
         targetSdk = libs.versions.android.targetSdk.get().toInt()
         versionCode = 1
         versionName = "1.0"
+
+        ndk {
+            abiFilters += listOf("arm64-v8a", "armeabi-v7a")
+        }
     }
+
+    buildTypes {
+        release {
+            isMinifyEnabled = true
+            isShrinkResources = true
+            proguardFiles(
+                getDefaultProguardFile("proguard-android-optimize.txt"),
+                "proguard-rules.pro"
+            )
+            signingConfig = signingConfigs.getByName("debug")
+        }
+    }
+
+    buildFeatures {
+        buildConfig = false
+    }
+
     compileOptions {
         sourceCompatibility = JavaVersion.VERSION_17
         targetCompatibility = JavaVersion.VERSION_17

androidApp/proguard-rules.pro

@@ -0,0 +1,20 @@
+# Kotlin Metadata (required for KMP)
+-keep class kotlin.Metadata { *; }
+-keepattributes *Annotation*, Signature, InnerClasses, EnclosingMethod
+
+# kotlinx.datetime
+-keep class kotlinx.datetime.** { *; }
+
+# tyme4kt (Chinese traditional calendar)
+-keep class cn.tyme.** { *; }
+
+# Compose runtime reflective lookups
+-keep class androidx.compose.runtime.** { *; }
+
+# ViewModel (used by CalendarViewModel)
+-keep class * extends androidx.lifecycle.ViewModel { *; }
+
+# Keep entry point composables referenced by string name
+-keepclassmembers class * {
+    @androidx.compose.runtime.Composable <methods>;
+}

gradle.properties

@@ -6,11 +6,14 @@ kotlin.daemon.jvmargs=-Xmx3072M
 org.gradle.jvmargs=-Xmx4096M -Dfile.encoding=UTF-8
 org.gradle.configuration-cache=true
 org.gradle.caching=true
+org.gradle.parallel=true
+org.gradle.daemon=true
 
 #Android
 android.nonTransitiveRClass=true
 android.useAndroidX=true
 android.uniquePackageNames=false
 android.dependency.useConstraints=true
-android.r8.strictFullModeForKeepRules=false
+android.r8.strictFullModeForKeepRules=true
 android.generateSyncIssueWhenLibraryConstraintsAreEnabled=false
+android.enableR8.fullMode=true