chore(docker): expose 3000 and honor with default; avoid conflicting port assumptions

Dockerfile

@@ -14,14 +14,12 @@ COPY --chown=1000 . .
 # Build the app
 RUN npm run build
 
-# Expose the port expected by Hugging Face Docker Spaces
-EXPOSE 7860
+# Expose default Next.js port; runtime will honor $PORT
+EXPOSE 3000
 
 ENV HOST=0.0.0.0
-# Default to the Space port, but allow HF to override
-ENV PORT=7860
 # Disable telemetry and ensure production env
 ENV NEXT_TELEMETRY_DISABLED=1
 ENV NODE_ENV=production
-# Run Next directly and honor $PORT
-CMD ["sh", "-c", "node node_modules/next/dist/bin/next start -H 0.0.0.0 -p ${PORT}"]
+# Run Next directly and honor $PORT, defaulting to 3000
+CMD ["sh", "-c", "node node_modules/next/dist/bin/next start -H 0.0.0.0 -p ${PORT:-3000}"]