chore: Upgrade website to Docsy 0.15.0

[markmandel]

Summary

Upgrade the Agones website from Docsy v0.14.3 to v0.15.0. This also requires bumping the Hugo version in the build image from 0.152.2 to 0.157.0.

Changes Required

File	Change
site/go.mod	Bump github.com/google/docsy from v0.14.3 → v0.15.0
site/go.sum	Regenerate via cd site && go mod tidy
build/build-image/Dockerfile	Bump HUGO_VER from 0.152.2 → 0.157.0

New Features in 0.15.0

• Agent support (experimental): Generates llms.txt and Markdown page output to help AI tools consume documentation
• Doc-rooted sites (experimental): Publish docs at the root URL (e.g. /get-started/) instead of under /docs/
• Enhanced version menu: Supports headings, separators, per-entry page-link behaviour, and kind-specific styling

Breaking Changes to Review

• Version menu markup: Updated HTML markup and CSS classes; the version menu is no longer hidden on smaller viewports — check any custom CSS or layout overrides targeting the old classes
• Card shortcode: Arguments now processed with RenderString instead of markdownify — low risk, but verify any card shortcode usage renders correctly
• Multilingual links: Not applicable (Agones site is English-only)

Acceptance Criteria

• Update site/go.mod and run cd site && go mod tidy
• Update HUGO_VER in build/build-image/Dockerfile
• From the build/ directory, run make site-server and open http://localhost:1313 — verify the site renders correctly
• Check the version menu renders correctly on desktop and mobile viewports
• Check any pages using the card shortcode render correctly

[Cloud-Architect-Emma]

Hi @markmandel , I've opened this PR to address #4586. All three required changes are in place: Docsy bumped to v0.15.0, go.sum regenerated via go mod tidy, and Hugo version bumped to 0.157.0 in the Dockerfile.

Happy to make any adjustments if needed.
Thanks!

[narutamaaurum]

Opened PR #4594 to upgrade Docsy from v0.14.3 to v0.15.0 and Hugo from 0.152.2 to 0.157.0. go.sum was regenerated cleanly via go mod tidy.

[Cloud-Architect-Emma]

Hi @markmandel, just to note that PR #4593 was opened before #4594 and contains the same changes.

Happy to have either merged, but wanted to flag the duplication so you can choose which to review.

Thanks!

[markmandel]

Let's goooooooo 😄

[markmandel]

@narutamaaurum , @Cloud-Architect-Emma - Thanks for work!

I was digging into https://www.docsy.dev/blog/2026/0.15.0/#agent-support - and it would be lovely to see at least the llms.txt in the generated preview.

I expect app engine is not setup to pick up the llms.txt -- also wondering if we want to attempt some or all of the new features as well in this PR, see how well it works.

What do you think - shall we try it in these PRs? Whichever you want to take it for a spin?

[Cloud-Architect-Emma]

Hi @markmandel, I'd love to explore the new features but I'd prefer to keep this PR focused on the version bump as scoped in #4586 to keep the review clean. Happy to open a follow-up PR to experiment with llms.txt and the other Docsy 0.15.0 features once this lands.

Would that work for you?

[markmandel]

Hi @markmandel, I'd love to explore the new features but I'd prefer to keep this PR focused on the version bump as scoped in #4586 to keep the review clean. Happy to open a follow-up PR to experiment with llms.txt and the other Docsy 0.15.0 features once this lands.

Would that work for you?

Testing the AI features looks to be basically a 1 line change in the config file. Without trying out these features, not sure there is a huge benefit to upgrading, and it's a small change - so I feel like we should include enabling the AI changes and see how they work out.

So some experimentation is required for this work please!