feat: 完成 Mini Swap DEX AMM 项目开发

- 添加智能合约: TokenA, TokenB, MiniSwapAMM
- 实现 AMM 流动性池功能 (x * y = k 公式)
- 支持添加/移除流动性和代币交换
- 包含完整的测试套件
- 创建 React 前端界面，支持钱包连接
- 添加 Web3 集成和现代化 UI 设计
- 包含部署脚本和完整的项目配置

.gitignore

@@ -0,0 +1,142 @@
+# Dependencies
+node_modules/
+frontend/node_modules/
+
+# Build outputs
+dist/
+build/
+frontend/build/
+frontend/dist/
+
+# Hardhat files
+cache/
+artifacts/
+typechain-types/
+
+# Contract deployment addresses (optional, 根据需要决定是否忽略)
+# contract-addresses.json
+
+# Environment variables
+.env
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+
+# Logs
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+lerna-debug.log*
+*.log
+
+# Runtime data
+pids
+*.pid
+*.seed
+*.pid.lock
+
+# Coverage directory used by tools like istanbul
+coverage/
+*.lcov
+.nyc_output
+
+# IDE and editor files
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# OS generated files
+.DS_Store
+.DS_Store?
+._*
+.Spotlight-V100
+.Trashes
+ehthumbs.db
+Thumbs.db
+
+# Temporary folders
+tmp/
+temp/
+
+# Optional npm cache directory
+.npm
+
+# Optional eslint cache
+.eslintcache
+
+# Microbundle cache
+.rpt2_cache/
+.rts2_cache_cjs/
+.rts2_cache_es/
+.rts2_cache_umd/
+
+# Optional REPL history
+.node_repl_history
+
+# Output of 'npm pack'
+*.tgz
+
+# Yarn Integrity file
+.yarn-integrity
+
+# parcel-bundler cache (https://parceljs.org/)
+.cache
+.parcel-cache
+
+# Next.js build output
+.next
+
+# Nuxt.js build / generate output
+.nuxt
+
+# Gatsby files - 只忽略根目录的 public 文件夹，不影响 frontend/public
+/public
+
+# Storybook build outputs
+.out
+.storybook-out
+
+# Rollup.js default build output
+dist/
+
+# Uncomment if using Webpack
+# webpack-stats.json
+
+# TypeScript compiled output
+*.tsbuildinfo
+
+# Optional stylelint cache
+.stylelintcache
+
+# SvelteKit build / generate output
+.svelte-kit
+
+# Local netlify folder
+.netlify
+
+# Hardhat Network files (if using Hardhat Network)
+hardhat-network-helpers/
+
+# Test files (optional)
+# test-results/
+# playwright-report/
+
+# Solidity coverage files
+coverage.json
+coverage/
+
+# Certora prover output
+.certora_verify_cache/
+.certora_config/
+
+# Gas reporter output
+gas-report.txt
+
+# Slither analysis output
+slither-report.json
+
+# Echidna
+crytic-export/