Pin kaleido<1.0 in both containers to fix ChromeNotFoundError

[mmcky]

Problem

The container tests (test-containers-lectures.yml) fail at notebook execution with ChromeNotFoundError from kaleido on Plotly static-image export — BCG_complete_mkts.md, BCG_incomplete_mkts.md, knowing_forecasts_of_others.md. This is the same "unpinned dependency bumped a major" class as #28.

Root cause

kaleido was pip-installed unpinned and resolved to v1.x (currently 1.3.0). kaleido v1 dropped the self-contained chromium and requires a separately provisioned Chrome. Both Dockerfiles ran kaleido.get_chrome_sync() at build time — but that downloads Chrome under /root/.cache (build runs as root), while GitHub Actions container jobs run with HOME=/github/home, so at test runtime kaleido looks in the wrong place and can't find Chrome.

Fix

• Pin kaleido<1.0 in both containers/quantecon/environment.yml and containers/quantecon-build/environment.yml.
• Drop the now-invalid kaleido.get_chrome_sync() build step from both Dockerfiles (v0 has no such API; leaving it would fail the build).

kaleido 0.2.x bundles its own chromium inside the package (location-independent, so the HOME difference is irrelevant) and still exports images on the current plotly. The existing apt chromium runtime libs (libnss3, libgbm1, libasound2t64, …) are retained for the bundled browser.

Verification

Installed plotly==6.7.0 (the version the lean image resolves) + kaleido==0.2.1 on Python 3.13 and exported a PNG:

plotly 6.7.0 | kaleido 0.2.1
to_image(engine=kaleido) OK -> 23957 bytes

Only DeprecationWarnings are emitted (Plotly notes kaleido v0 support is deprecated) — no error. The full image's plotly 6.3.0 is older and on the same deprecation (warn, not error) path.

Caveat / follow-up

This is a pragmatic stopgap consistent with long-standing QuantEcon practice: kaleido v0 is deprecated by Plotly, so a future Plotly release could eventually drop it. Migrating to kaleido v1 with a system-provisioned Chrome (install google-chrome/chromium to a fixed path and point kaleido at it via env, independent of HOME) is the durable path and is left as a follow-up.

Notes

• Separate from and complementary to Pin lean container's science stack to the Anaconda 2025.12 baseline (#28) #84 (which pinned the science stack). With both merged, the container test workflow should go green.
• The ubuntu:24.04 base-image "high vulnerability" warning surfaced by the IDE is pre-existing and unrelated to this change.

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR stabilizes Plotly static-image export in the quantecon and quantecon-build container images by preventing kaleido from upgrading to v1.x (which requires an externally provisioned Chrome) and by removing the now-invalid build-time Chrome download step.

Changes:

• Pin kaleido<1.0 in both container environment.yml files to keep using kaleido v0.x (bundled chromium).
• Remove the kaleido.get_chrome_sync() build step from both container Dockerfiles.
• Document the fix and rationale in CHANGELOG.md under Unreleased → Fixed.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
containers/quantecon/environment.yml	Pin kaleido<1.0 in pip deps with rationale for CI runtime HOME behavior.
containers/quantecon/Dockerfile	Remove build-time kaleido.get_chrome_sync() invocation.
containers/quantecon-build/environment.yml	Pin kaleido<1.0 in pip deps with matching rationale.
containers/quantecon-build/Dockerfile	Remove build-time kaleido.get_chrome_sync() invocation.
CHANGELOG.md	Add Unreleased changelog entry describing the kaleido pin + removed Chrome download step.