fix(devcontainers): replace broken packages, improve usability

[JonAnCla]

Description of changes

I've found devcontainers to be particularly useful for local development with AI tools (to reduce risk of them doing something damaging or exfiltrating other files on your system)

In trying to use the existing devcontainer config in ibis, I found following issues:

• openjdk-17-jdk is not present on base python image
• file edits made within container were not reflected back to the host
• RUN chown ... command is very slow
• duckdb-cli feature no longer builds with duckdb 1.5.x version

Changes below were made (I guided Claude) to address the above

Dockerfile

• Replace openjdk-17-jdk with default-jdk so the correct JDK is selected regardless of the underlying Debian version.
• Move the venv from /app/.venv to /opt/venv (via ENV VIRTUAL_ENV=/opt/venv). Because /opt/venv is outside the workspace mount point, the venv survives the bind-mount and remains usable at runtime. The editable ibis install inside the venv still points to /app, so it picks up live source changes from the host.
• Use COPY --chown=$USERNAME . /app to set file ownership in a single pass, replacing the separate RUN chown -R $USERNAME /app step.
• Remove the no-op SHELL ["/bin/bash", "-c", "source .venv/bin/activate"] directive — SHELL only affects subsequent RUN instructions during the build; it does not activate the venv at container runtime.
• Remove the now-redundant VENV_DIR and IBIS_PROJECT env vars.

devcontainer.json

• Add an explicit workspaceMount so the host workspace is always bind-mounted to /app, in both local VS Code and Codespaces.
• Remove duckdb-cli devcontainer feature as it no longer builds

Thanks!

[JonAnCla]

sorry for typo in title (fic should be fix)
:(