Add video optimization and following-first feed

Dockerfile

@@ -13,6 +13,9 @@ FROM node:20-alpine AS runner
 WORKDIR /app
 
 ENV NODE_ENV=production
+ENV VIDEO_PROCESSING_FFMPEG_PATH=/usr/bin/ffmpeg
+
+RUN apk add --no-cache ffmpeg
 
 COPY package*.json ./
 RUN npm ci --omit=dev
@@ -21,4 +24,4 @@ COPY --from=builder /app/dist ./dist
 
 EXPOSE 4000
 
-CMD ["node", "dist/main.js"]
+CMD ["node", "dist/main.js"]