fix: 修复构建配置和运行时错误处理

backend/Dockerfile

@@ -11,7 +11,7 @@ ARG GO_VERSION=1.24.5
 ARG GOPROXY=https://goproxy.cn,direct
 ARG GOSUMDB=sum.golang.google.cn
 
-FROM golang:${GO_VERSION} AS build
+FROM golang:${GO_VERSION} AS deps
 ARG GOPROXY
 ARG GOSUMDB
 ENV GOPROXY=${GOPROXY} \
@@ -24,12 +24,17 @@ RUN --mount=type=cache,target=/go/pkg/mod \
     --mount=type=cache,target=/root/.cache/go-build \
     go mod download
 
+FROM deps AS source
 COPY backend/ ./
 
 ENV CGO_ENABLED=0
+
+FROM source AS api-build
 RUN --mount=type=cache,target=/go/pkg/mod \
     --mount=type=cache,target=/root/.cache/go-build \
     go build -trimpath -ldflags="-s -w" -o /out/api ./cmd
+
+FROM source AS worker-build
 RUN --mount=type=cache,target=/go/pkg/mod \
     --mount=type=cache,target=/root/.cache/go-build \
     go build -trimpath -ldflags="-s -w" -o /out/worker ./cmd/worker
@@ -37,15 +42,15 @@ RUN --mount=type=cache,target=/go/pkg/mod \
 FROM alpine:3.21 AS base
 RUN apk add --no-cache ca-certificates tzdata && adduser -D -H -s /sbin/nologin app
 WORKDIR /app
-COPY --from=build /src/backend/configs ./configs
+COPY --from=source /src/backend/configs ./configs
 RUN mkdir -p ./.run/uploads && chown -R app:app /app
 USER app
 
 FROM base AS api
-COPY --from=build /out/api /app/api
+COPY --from=api-build /out/api /app/api
 EXPOSE 8080
 ENTRYPOINT ["/app/api"]
 
 FROM base AS worker
-COPY --from=build /out/worker /app/worker
+COPY --from=worker-build /out/worker /app/worker
 ENTRYPOINT ["/app/worker"]