feat(docker): update Docker configuration and add build workflow

Dockerfile

@@ -0,0 +1,35 @@
+FROM node:22-bookworm-slim
+
+# Runtime deps: ffmpeg for video muxing, yt-dlp for download, build tools for node-canvas
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    ffmpeg \
+    python3 \
+    curl \
+    ca-certificates \
+    git \
+    make \
+    g++ \
+    && rm -rf /var/lib/apt/lists/*
+
+# yt-dlp
+RUN curl -L https://github.com/yt-dlp/yt-dlp/releases/latest/download/yt-dlp \
+    -o /usr/local/bin/yt-dlp && chmod a+rx /usr/local/bin/yt-dlp
+
+RUN corepack enable
+
+WORKDIR /app
+
+# Install deps from the app-local build context.
+COPY package.json pnpm-lock.yaml pnpm-workspace.yaml* ./
+COPY vendor/discord-video-stream/package.json ./vendor/discord-video-stream/
+COPY vendor/discord.js-selfbot-v13/package.json ./vendor/discord.js-selfbot-v13/
+RUN pnpm install --no-frozen-lockfile
+
+COPY . .
+
+RUN pnpm run prepare:vendor
+RUN pnpm run build
+
+ENV NODE_ENV=production
+
+CMD ["pnpm", "run", "start"]