Move `npm run build` out of the Docker image onto the runner, where actions/cache persists .next/cache across runs (the in-Docker build discarded it every time). The image now just packages the prebuilt .next and serves it with `next start`; runtime and the DocSearch entrypoint injection are unchanged.
Also: checkout full history (fetch-depth: 0) so per-page dates are correct, guard buildGitDateMap against shallow clones (correct-or-absent, never wrong), modernise the Docker actions (build-push-action v6, provenance: false), and add a path-filtered pull_request trigger so pipeline changes are validated before merge.
Smoke-tested via isolated build + docker run: serves /, /introduction, /api, sitemap, static assets (200); DocSearch placeholder injection intact.
Replace ~314 `git log` spawns per gen script with a single `git log --name-only` pass, memoised per process. Cuts gen:last-updated + gen:sitemap from ~15s to ~1.5s.
Output is byte-identical to the per-file version; still degrades to no-dates when git is unavailable (e.g. the Docker image).
* ci: validate PRs with build and MDX heading linter
Adds a pull_request workflow running npm run lint:mdx, npm run build,
and npm run lint so heading-hierarchy bugs and broken builds get caught
before merge rather than after.
The new linter (scripts/lint-mdx-headings.mjs) enforces that the first
heading is h1 and that heading levels never jump by more than one. Also
fixes three existing pages that had no h1 title — two were using a
legacy export const title pattern, one was missing a title entirely.
* ci: use npm install since lockfile is gitignored
package-lock.json is in .gitignore, so npm ci and setup-node's npm
cache both fail on a fresh CI checkout. Match the Dockerfile pattern
(npm install, no cache) instead.
* ci: drop ESLint step; project config is broken
`npm run lint` fails with 'Converting circular structure to JSON'
under ESLint 9.x — the repo has no .eslintrc or eslint.config file,
so the legacy resolver hits the React plugin's circular reference.
This is pre-existing (build_n_push.yml never ran lint, so it stayed
hidden); fixing it needs flat-config migration and is out of scope.
Drop the step until that lands.
* Add script to generate sitemap.xml and update related configurations
* chore: add robots.txt referencing sitemap.xml
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Co-authored-by: Jack Carter <128555021+SunsetDrifter@users.noreply.github.com>
