CI: Add Dockerfile

This is used as the runtime image for the Discord bot.

Dockerfile

@@ -0,0 +1,36 @@
+ARG BUN_VERSION="1.1.38"
+
+# --- Build container ---
+FROM oven/bun:${BUN_VERSION}-slim AS build
+
+ARG REVISION="master"
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+RUN apt-get update \
+    && apt-get install -y build-essential git python3
+
+RUN mkdir /app \
+    && cd /app \
+    && git clone https://github.com/LadybirdBrowser/discord-bot.git \
+    && cd discord-bot \
+    && git checkout "${REVISION}" \
+    && rm -rf .git \
+    && bun install
+
+# --- Runtime image ---
+FROM oven/bun:${BUN_VERSION}-slim
+
+LABEL maintainer="Ladybird Browser Initiative <[email protected]>"
+
+RUN mkdir /app
+COPY --from=build /app/discord-bot /app/discord-bot
+
+RUN useradd discord-bot \
+    && chown -R discord-bot:discord-bot /app/discord-bot
+
+USER discord-bot
+WORKDIR /app/discord-bot
+
+ENTRYPOINT [ "/usr/local/bin/bun" ]
+CMD [ "start" ]