chore: add Dockerfile

Dockerfile

@@ -0,0 +1,43 @@
+FROM rust:1.83-alpine3.21 AS builder
+
+ARG DI_VER=1.2.5
+
+WORKDIR /app
+
+RUN apk update && apk add --no-cache build-base
+
+# Build dumb-init
+RUN wget -O - "https://github.com/Yelp/dumb-init/archive/refs/tags/v${DI_VER}.tar.gz" | tar -xzf - && \
+    cd "dumb-init-${DI_VER}" && \
+    make SHELL=/bin/sh && \
+    mv dumb-init .. && \
+    cd ..
+
+COPY Cargo.toml Cargo.lock ./
+
+RUN cargo fetch --locked
+
+COPY . ./
+
+RUN cargo build --release --frozen
+
+
+FROM alpine:3.21
+
+COPY --from=builder /app/target/release/calathea /bin/calathea
+COPY --from=builder /app/dumb-init /bin/dumb-init
+
+# Create a non-root user & make sure it can write to the data directory
+RUN set -x && \
+	adduser -u 82 -D -S -G www-data www-data && \
+    mkdir /data && \
+    chown -R www-data:www-data /data
+
+WORKDIR /data
+
+USER www-data:www-data
+
+ENTRYPOINT [ "/bin/dumb-init", "--" ]
+CMD [ "/bin/calathea" ]
+
+