feat: add docker build

Dockerfile

@@ -0,0 +1,42 @@
+FROM golang:1.26.0-alpine AS go_builder
+
+RUN apk update && apk upgrade && \
+    apk add --no-cache ca-certificates tzdata git && \
+    update-ca-certificates
+
+WORKDIR /src
+
+COPY go.mod go.sum ./
+
+RUN --mount=type=cache,target=/go/pkg/mod \
+    --mount=type=cache,target=/root/.cache/go-build \
+    go mod download && go mod verify
+
+COPY . .
+
+RUN --mount=type=cache,target=/go/pkg/mod \
+    --mount=type=cache,target=/root/.cache/go-build \
+    CGO_ENABLED=0 GOOS=linux \
+    go build -trimpath -ldflags="-w -s" \
+    -o /app/ristek-task-be-bagas \
+    .
+
+RUN adduser -D -u 10001 -g '' appuser && \
+    mkdir -p /app/certs/ssh /app/certs/tls && \
+    chown -R appuser:appuser /app
+
+FROM scratch
+
+COPY --from=go_builder /usr/share/zoneinfo /usr/share/zoneinfo
+COPY --from=go_builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
+COPY --from=go_builder /etc/passwd /etc/passwd
+COPY --from=go_builder /etc/group /etc/group
+COPY --from=go_builder --chown=appuser:appuser /app /app
+
+WORKDIR /app
+
+USER appuser
+
+ENV TZ=Asia/Jakarta
+
+ENTRYPOINT ["/app/ristek-task-be-bagas"]