feat(docker): add python3 and pip to base image

Replaces python3-minimal with full python3 and adds python3-pip so
agents can install and run Python packages. Enterprise inherits this
from the base image.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Juan Roldan

infra/Dockerfile

@@ -9,7 +9,8 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
       chromium \
       curl \
       ffmpeg \
-      python3-minimal \
+      python3 \
+      python3-pip \
       fonts-liberation \
       libasound2 \
       libatk-bridge2.0-0 \