chore: 添加 CI 工具链 — golangci-lint + gofumpt + goimports + Makefile

.golangci.yml:
  - 启用 linter: errcheck, gosec, govet, staticcheck, ineffassign, unused,
    revive, contextcheck, errorlint, errname, misspell
  - 启用 formatter: gofumpt + goimports

Makefile:
  - fmt/fmt-check: gofumpt + goimports 格式检查
  - lint/lint-strict: golangci-lint 报告/阻断模式
  - test: go test -race
  - ci: 完整 CI 流程 (fmt-check + lint)

docs/code-style.md:
  - 新增 AI 执行协议 + 代码格式化/自动化检查/MUST规则
  - 集成 golangci-lint 检查项与规范对照

scripts/ci.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+# CI 流水线脚本
+# 调用方式：bash scripts/ci.sh [--strict]
+#   --strict  阻断模式（lint 失败则 exit 1）
+#   默认      报告模式（lint 只输出不阻断）
+
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+export PATH="$HOME/go/bin:$PATH"
+
+cd "$ROOT"
+
+STRICT=false
+if [[ "${1:-}" == "--strict" ]]; then
+    STRICT=true
+fi
+
+echo "========================================"
+echo "  CI Pipeline"
+echo "  Mode: $( $STRICT && echo 'STRICT' || echo 'REPORT' )"
+echo "========================================"
+
+# 1. 格式检查
+echo ""
+echo "==> 1/3 格式检查 (gofumpt + goimports)"
+make fmt-check
+
+# 2. 编译检查
+echo ""
+echo "==> 2/3 编译检查 (go build)"
+go build ./...
+
+# 3. 静态分析
+echo ""
+echo "==> 3/3 静态分析 (golangci-lint)"
+if $STRICT; then
+    make lint-strict
+else
+    make lint
+fi
+
+echo ""
+echo "========================================"
+echo "  CI Pipeline 完成"
+echo "========================================"