Add an emacs script to export a single page to HTML

compass build --direct site only ever runs the full org-publish-project defined in projects/ores.lisp/src/ores-build-site.el (site:pages + site:images + site:style + site:pdf, ~4368 org-roam nodes) — there is no single-file target in either compass.py's EMACS_BUILD_SCRIPTS=/=BUILD_TARGET_ALIASES or the elisp itself, confirmed while trying to speed up an iterative release-notes review (each full rebuild took 3-5+ minutes, killed and re-run several times during one review session). Add a new script (e.g. ores-build-page.el) that takes a file path (via command-line-args-left, following the pattern the other ores-build-*.el scripts use for their own args) and calls (org-publish-file FILE (assoc "site:pages" org-publish-project-alist) t) — reusing the exact same publishing function, preamble, and options as the full site build, just scoped to one file. Wire it into compass.py as a new --direct target, e.g. compass build --direct page <path> or compass site show-html <path>, alongside the existing deploy_site entry.

Reviewing a single doc (release notes, a story, a recipe) after every edit currently means waiting out a full site rebuild whose cost is almost entirely the other ~4000+ unrelated pages and the org-roam graph JSON regeneration. A single-file export would make the edit/preview loop during any doc-review session (release notes, manual chapters, knowledge docs) fast enough to actually iterate against, rather than batching several edits before rebuilding.

• projects/ores.lisp/src/ores-build-site.el — the org-publish-project-alist (site:pages entry) and ores/site-preamble to reuse.
• projects/ores.compass/src/compass.py — EMACS_BUILD_SCRIPTS=/=BUILD_TARGET_ALIASES (~line 5510-5533), where the new target would be wired in.