feat(codespaces): auto-setup Python venv with dependencies (#34409)

Co-authored-by: Claude <noreply@anthropic.com>

.devcontainer/Dockerfile

@@ -0,0 +1,20 @@
+# Keep this in sync with the base image in the main Dockerfile (ARG PY_VER)
+FROM python:3.11.13-bookworm AS base
+
+# Install system dependencies that Superset needs
+# This layer will be cached across Codespace sessions
+RUN apt-get update && apt-get install -y \
+    libsasl2-dev \
+    libldap2-dev \
+    libpq-dev \
+    tmux \
+    gh \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install uv for fast Python package management
+# This will also be cached in the image
+RUN curl -LsSf https://astral.sh/uv/install.sh | sh && \
+    echo 'export PATH="/root/.cargo/bin:$PATH"' >> /etc/bash.bashrc
+
+# Set the cargo/bin directory in PATH for all users
+ENV PATH="/root/.cargo/bin:${PATH}"