feat: add noVNC headed mode for interactive browser sessions

- Dockerfile with Xvfb + x11vnc + noVNC for browser-in-a-URL
- search.py auto-detects DISPLAY env to run headed vs headless
- pause_for_human() function for CAPTCHA/login handoff
- Facebook Marketplace search (headed mode only, needs login)
- Updated README with both modes

entrypoint.sh

@@ -0,0 +1,28 @@
+#!/bin/bash
+set -e
+
+# Start virtual display
+export DISPLAY=:99
+Xvfb :99 -screen 0 1280x720x24 -ac &
+sleep 1
+
+# Start VNC server on the virtual display (no password, listen on 5900)
+x11vnc -display :99 -forever -nopw -listen 0.0.0.0 -rfbport 5900 -shared &
+sleep 1
+
+# Start noVNC web proxy (serves browser view at http://localhost:6080/vnc.html)
+websockify --web=/usr/share/novnc/ 6080 localhost:5900 &
+sleep 1
+
+echo "============================================="
+echo "  noVNC ready: http://localhost:6080/vnc.html"
+echo "============================================="
+
+# Run whatever command was passed (or drop to shell)
+if [ $# -eq 0 ]; then
+    echo "No command given. Container is running -- attach to use."
+    echo "Run searches with: docker exec car-help uv run python search.py"
+    tail -f /dev/null
+else
+    exec "$@"
+fi