chore: 添加 macOS/Web 平台支持 + 修复编译错误 + 开发环境文档

- 修复 CardTheme → CardThemeData（Flutter 3.41 API 变更）
- 修复 finance_screen 缺少 FormDialog import
- 修复工具栏 Row overflow（添加横向滚动）
- flutter create --platforms=macos,web 生成平台配置
- 添加 docs/dev-setup.md：完整开发环境配置指南
  含 Go/Flutter/Docker 安装、已知 macOS 26 兼容问题及解决方案

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/.metadata

@@ -0,0 +1,30 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: "db50e20168db8fee486b9abf32fc912de3bc5b6a"
+  channel: "stable"
+
+project_type: app
+
+# Tracks metadata for the flutter migrate command
+migration:
+  platforms:
+    - platform: root
+      create_revision: db50e20168db8fee486b9abf32fc912de3bc5b6a
+      base_revision: db50e20168db8fee486b9abf32fc912de3bc5b6a
+    - platform: web
+      create_revision: db50e20168db8fee486b9abf32fc912de3bc5b6a
+      base_revision: db50e20168db8fee486b9abf32fc912de3bc5b6a
+
+  # User provided section
+
+  # List of Local paths (relative to this file) that should be
+  # ignored by the migrate tool.
+  #
+  # Files that are not part of the templates will be ignored by default.
+  unmanaged_files:
+    - 'lib/main.dart'
+    - 'ios/Runner.xcodeproj/project.pbxproj'