chore(docker): add Dockerfile for container builds

.dockerignore

@@ -0,0 +1,13 @@
+/target
+.git
+.github
+.claude
+.idea
+.vscode
+*.swp
+*.swo
+.DS_Store
+.env
+.env.*
+tests/
+criterion/

Dockerfile

@@ -0,0 +1,55 @@
+# === Build stage ===
+FROM rust:1-bookworm AS builder
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    protobuf-compiler \
+    clang \
+    libclang-dev \
+    && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+
+# Copy dependency manifests first to leverage Docker layer caching
+COPY Cargo.toml Cargo.lock ./
+# Create dummy files to trigger dependency download
+RUN mkdir -p src/bin/aether-bench && \
+    echo "fn main(){}" > src/main.rs && \
+    echo "fn main(){}" > src/bin/aether-bench/main.rs && \
+    echo "fn main(){}" > build.rs && \
+    mkdir benches && \
+    echo "fn main(){}" > benches/storage.rs && \
+    echo "fn main(){}" > benches/raft_store.rs && \
+    echo "fn main(){}" > benches/codec.rs && \
+    mkdir proto && touch proto/kv.proto proto/cluster.proto proto/raft.proto \
+        proto/watch.proto proto/lease.proto proto/auth.proto proto/shard.proto \
+        proto/maintenance.proto proto/lock.proto proto/election.proto \
+        proto/barrier.proto proto/queue.proto proto/session.proto && \
+    cargo build --release && \
+    rm -rf src build.rs benches proto
+
+# Copy source and proto files, then rebuild
+COPY build.rs ./
+COPY benches/ benches/
+COPY proto/ proto/
+COPY src/ src/
+RUN touch build.rs src/main.rs && cargo build --release
+
+# === Runtime stage ===
+FROM debian:bookworm-slim AS runtime
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    ca-certificates \
+    && rm -rf /var/lib/apt/lists/*
+
+RUN groupadd -r aether && useradd -r -g aether -d /data aether
+
+COPY --from=builder /app/target/release/aether /usr/local/bin/aether
+
+RUN mkdir -p /data && chown aether:aether /data
+
+USER aether
+WORKDIR /data
+
+EXPOSE 2379 2380 9090
+
+ENTRYPOINT ["aether"]