chore: 初始化脚手架 — sunny_mochi 企业级 Flutter 模板

Core 基础设施：Flavor 三包体系、Drift+SQLCipher 加密数据库
7 拦截器 Dio 网络栈、CrashReporter 崩溃日志、Sealed Failure 错误体系
5 色板主题系统、Auth 认证骨架（Clean Architecture）、Dev Panel、Mock Adapter

通过验证：flutter analyze（0 errors）、flutter test（全绿）、staging APK 74.8MB

Makefile

@@ -0,0 +1,50 @@
+FLUTTER := flutter
+
+.PHONY: help run-dev run-staging build-staging build-prod build-apk-dev clean gen gen-i18n
+
+help:
+	@echo "Flutter Flavor 构建命令："
+	@echo ""
+	@echo "  make run-dev        开发版调试运行（热重载，连 dev 服务器）"
+	@echo "  make run-staging    测试版 Release 运行（连 test 服务器）"
+	@echo "  make build-staging  打测试版 APK（给测试团队安装）"
+	@echo "  make build-prod     打正式版 AAB（上 Play Store / 内部分发）"
+	@echo "  make build-apk-dev  打开发版 APK（快速真机验证）"
+	@echo "  make clean          清除构建缓存"
+	@echo "  make gen            代码生成（build_runner）"
+	@echo "  make gen-i18n       生成 i18n ARB → Dart"
+	@echo ""
+	@echo "注意：build-prod 需先复制 dart-defines/prod.json.template 为 dart-defines/prod.json 并填入真实密钥"
+
+run-dev:
+	$(FLUTTER) run --flavor dev \
+		--dart-define-from-file=dart-defines/dev.json
+
+run-staging:
+	$(FLUTTER) run --flavor staging --release \
+		--dart-define-from-file=dart-defines/staging.json
+
+build-apk-dev:
+	$(FLUTTER) build apk --flavor dev --debug \
+		--dart-define-from-file=dart-defines/dev.json
+
+build-staging:
+	$(FLUTTER) build apk --flavor staging --release \
+		--dart-define-from-file=dart-defines/staging.json
+	@echo "APK 路径：build/app/outputs/flutter-apk/app-staging-release.apk"
+
+build-prod:
+	@test -f dart-defines/prod.json || \
+		(echo "ERROR: dart-defines/prod.json 不存在！请从 prod.json.template 复制并填入真实密钥。" && exit 1)
+	$(FLUTTER) build appbundle --flavor prod --release \
+		--dart-define-from-file=dart-defines/prod.json
+	@echo "AAB 路径：build/app/outputs/bundle/prodRelease/app-prod-release.aab"
+
+clean:
+	$(FLUTTER) clean
+
+gen:
+	dart run build_runner build --delete-conflicting-outputs
+
+gen-i18n:
+	dart run slang