build(Dockerfile): 添加多平台构建支持并禁用CGO

添加TARGETOS、TARGETARCH和TARGETVARIANT构建参数以支持多平台构建
设置CGO_ENABLED=0以静态编译
优化构建命令以支持不同架构变体

Dockerfile

@@ -1,10 +1,13 @@
 FROM golang:1.21-alpine AS build
+ARG TARGETOS=linux
+ARG TARGETARCH=amd64
+ARG TARGETVARIANT=""
+ENV CGO_ENABLED=0
 WORKDIR /app
-RUN --mount=type=cache,target=/var/cache/apk apk add build-base
 COPY server/ ./server/
 COPY web/ ./web/
 WORKDIR /app/server
-RUN go build -o /app/bin/marketing-data-server ./cmd/server
+RUN GOOS=$TARGETOS GOARCH=$TARGETARCH GOARM=$(echo $TARGETVARIANT | sed 's/^v//') go build -o /app/bin/marketing-data-server ./cmd/server
 
 FROM alpine:3.19
 WORKDIR /app