Show project homepages in the Hydra Landscape

[adarshsm]

Closes #3375.

Landscape entries linked only to a repository. A listing may now also carry an optional homepage, shown beside the repository link; entries without one render exactly as before.

What changed

Stage	Change
refresh_landscape_metadata.py	Requests homepageUrl and records it verbatim apart from surrounding whitespace, so an unset homepage (GitHub returns null or "") becomes None.
build_landscape_review.py	Reports the homepage in the review queue — the point where a maintainer decides whether to promote it.
build_public_landscape.py	Accepts optional listing.homepage, requires HTTPS, rejects one that merely repeats listing.url, and omits the key entirely when absent.
validate-landscape.mjs	Tolerates the optional field and enforces the same two rules on generated data.
LandscapeDirectory	Renders a Homepage link next to the repository link when one exists.
data/decisions.json	Records the homepage GitHub reports for 61 of the 104 included projects.

The repository link is untouched and still present on every card.

Verification

• PYTHONPATH=tools/landscape pytest tools/landscape → 95 passed. Reverting the three tool changes makes 10 of the new tests fail, so they pin the new behaviour rather than passing vacuously.
• npm run validate:landscape passes. I also confirmed the new validator rules actually bite by mutating the generated file: a http:// homepage, a whitespace-only homepage, and a homepage equal to url each fail with the intended message; an unknown field is still rejected.
• npm run build succeeds and the built docs/landscape/index.html contains exactly 61 Homepage links, matching the 61 populated entries.
• Re-running the generator reproduces landscape.json byte-for-byte, and the decisions.json diff contains only added "homepage" lines.

Two curation calls that are yours, not mine

1. Ten of the 61 homepages are publications rather than project sites. These are what the projects themselves set on GitHub, so I recorded them faithfully, but a reader clicking "Homepage" may not expect a paper:

HazyResearch/hyena-dna, PRIME-RL/TTRL, SWivid/F5-TTS, SysCV/sam-pt, aiming-lab/SkillRL, pdebench/PDEBench (arXiv) · eloialonso/iris (OpenReview) · microsoft/mattergen (Nature) · mir-group/nequip (RSC) · langfengQ/verl-agent (HF papers). DBD-research-group/BirdSet points at a HF dataset.

Dropping them is a one-line filter in the ledger if you prefer. Note mir-group/nequip's URL returns 403 to automated probes — publisher bot protection, the page is real.

2. Three repositories declare an HTTP-only homepage and are therefore not included: dssg/aequitas and mees/calvin have no working HTTPS at all, so they are omitted rather than silently upgraded. hydra-ecosystem/hydra declares http://hydra.cc/, which does serve HTTPS, so it is recorded as https://hydra.cc/.

Smaller decisions worth a glance

• schemaVersion stays at 2. The field is purely additive and the only consumer ships in this repo. Happy to bump it if you would rather every shape change be visible.
• Homepages are not required to be unique, unlike name and url. Two listings from one monorepo can legitimately share a homepage, so I deliberately left them out of the uniqueness sets.
• The card keeps the repository slug as its repository link and adds a labelled Homepage beside it, which is the smallest change satisfying every bullet in the issue. If you would rather see two explicitly labelled Homepage / Repository links instead of the slug, that is a small edit to LandscapeCard.

[omry]

Thanks.

1. Did you note the CLA situation? are you okay with an upcoming CLA change?
2. Taking a look at the backlog atlas issue.
3. Please send screen shots of the home page and of the landscape
4. For projects that have a paper, maybe we can classify and use a different icon. A bit like the projects surface in my website