bci.place preview — stable redirect front

Stable front for the (ephemeral) Forester preview host of plurigrid/place PRs.

• Stable base: https://bmorphism.github.io/bci-preview/
• Any path is preserved and redirected to the live host listed in target.txt.
• The PRs (#25, #30) link here, so the links survive preview-host churn.

When the preview host changes

Update one file and push:

echo "https://files-morphvm-<newid>.http.cloud.morph.so" > target.txt
git commit -am "point at new preview host" && git push

404.html/index.html fetch target.txt client-side, so no HTML edits are needed.