chore: remove unused Dockerfile variants

Delete Dockerfile.minimal, Dockerfile.simple, and Dockerfile.binary
which were not referenced by CI, scripts, or documentation.
The production Dockerfile remains unchanged.

Co-Authored-By: Claude <noreply@anthropic.com>

proxy/Dockerfile.binary

@@ -1,19 +0,0 @@
-# Ultra-minimal Dockerfile using pre-built binary, no RUN commands
-FROM alpine:3.19
-
-LABEL maintainer="ardenone"
-LABEL description="Z.AI API proxy with token injection and Prometheus metrics"
-
-# Copy pre-built binary (statically linked or with minimal deps)
-COPY --chown=1000:1000 zai-proxy /zai-proxy
-
-# Alpine includes ca-certificates by default
-# Just need to set up non-root user
-USER 1000:1000
-
-EXPOSE 8080
-
-HEALTHCHECK --interval=30s --timeout=5s --start-period=5s --retries=3 \
-    CMD wget -q --spider http://localhost:8080/health || exit 1
-
-ENTRYPOINT ["/zai-proxy"]

proxy/Dockerfile.minimal

@@ -1,36 +0,0 @@
-# Minimal Dockerfile avoiding RUN commands that trigger overlayfs issues
-FROM docker.io/library/golang:1.23-alpine
-
-LABEL maintainer="ardenone"
-LABEL description="Z.AI API proxy with token injection and Prometheus metrics"
-
-WORKDIR /app
-
-# Copy go modules and source
-COPY go.mod go.sum* ./
-COPY *.go ./
-COPY VERSION ./
-
-# Build the binary (this RUN might work better than apk)
-RUN go mod download && \
-    VERSION=$(cat VERSION 2>/dev/null || echo "unknown") && \
-    COMMIT=${GIT_COMMIT:-$(git rev-parse HEAD 2>/dev/null || echo "unknown")} && \
-    BUILD_TIME=$(date -u +%Y-%m-%dT%H:%M:%SZ) && \
-    CGO_ENABLED=0 GOOS=linux go build -mod=mod \
-        -ldflags="-s -w -X main.version=$VERSION -X main.commit=$COMMIT -X main.buildTime=$BUILD_TIME" \
-        -o zai-proxy .
-
-# The golang:1.23-alpine image already has ca-certificates and apk
-RUN apk add --no-cache ca-certificates && \
-    adduser -D -u 1000 proxyuser && \
-    chmod +x zai-proxy && \
-    chown proxyuser:proxyuser zai-proxy
-
-USER proxyuser
-
-EXPOSE 8080
-
-HEALTHCHECK --interval=30s --timeout=5s --start-period=5s --retries=3 \
-    CMD wget -q --spider http://localhost:8080/health || exit 1
-
-ENTRYPOINT ["/zai-proxy"]

proxy/Dockerfile.simple

@@ -1,23 +0,0 @@
-# Simplified Dockerfile that avoids overlayfs mount issues
-# Uses single-stage build with pre-compiled binary
-
-FROM docker.io/library/alpine:3.19
-
-LABEL maintainer="ardenone"
-LABEL description="Z.AI API proxy with token injection and Prometheus metrics"
-
-# Install ca-certificates and create user in one layer
-RUN apk add --no-cache ca-certificates && \
-    adduser -D -u 1000 proxyuser
-
-# Copy pre-built binary
-COPY --chown=proxyuser:proxyuser zai-proxy /zai-proxy
-
-USER proxyuser
-
-EXPOSE 8080
-
-HEALTHCHECK --interval=30s --timeout=5s --start-period=5s --retries=3 \
-    CMD wget -q --spider http://localhost:8080/health || exit 1
-
-ENTRYPOINT ["/zai-proxy"]