docs: replace Gemini with Antigravity in the homepage hero - #66942

Visual Regression Check

All three captures returned 403 Forbidden (proxy "requested URL could not be retrieved") when browsing `(host.docker.internal/redacted) from the sandbox, so screenshots show the proxy error page and no visual comparison or accessibility audit was possible. This is an environment/proxy access issue, not a detected regression.

network:
  allowed:
    - defaults
    - "clients2.google.com"
    - "host.docker.internal"

Generated by 👁️ Visual Regression Checker for #66942 · copilot · auto · 12 AIC · ⌖ 0.568 AIC · ⊞ 7.7K · ◷

@copilot merge main and recompile

@copilot merge main and recompile

Merged main and ran make recompile successfully (333 workflows compiled). Merge commit: 4c35e19f77.

✅ Test Quality Sentinel completed test quality analysis.

No recognized test files (Go _test.go or JS .test.cjs/.test.js) were added or modified in this PR. The only test-related change, docs/tests/homepage-links.spec.ts, is a Playwright .spec.ts file outside the Test Quality Sentinel scoring scope, and all other changes are docs/marketing files (Astro components, MDX, TS logo config). Test Quality Sentinel skipped.

🧪 Test quality analysis by Test Quality Sentinel

@copilot address the following outstanding work in one pass:

1. Update this branch with the latest main using make merge-main, resolving any conflicts and preserving the intended changes.
2. Review (docs/src/components/CustomHead.astro:28): This changes the fallback used for OG/Twitter and JSON-LD, but Starlight's fallback at docs/astro.config.mjs:271 still says Gemini. filteredHead preserves meta[name="description"], so routes without their own description can now emit a Gemini standard description alongside Antigravity social descriptions. Update the Starlight default at the same time (ideally from one shared value) so fallback metadata remains consistent. - docs: replace Gemini with Antigravity in the homepage hero #66942 (comment)
3. Fix failing check agent (FAILURE): https://github.com/github/gh-aw/actions/runs/37865182159/job/113610765856.
4. Fix failing check conclusion (FAILURE): https://github.com/github/gh-aw/actions/runs/37865182159/job/113611775443.

Push the necessary fixes, reply to each listed review thread and resolve it when addressed. Ignore feedback already answered or resolved. Use the pr-finisher skill and stop when only human review or CI remains; do not trigger CI.

Sous-chef head: 4c35e19
Sous-chef work: 34f38971738f6a752a646bd7797a6c8d47fb096e4eb6f91e946a91255433c8c4 42df67b93ae93ccfb3eb6a907b0567591d2ab3ba01b3051a33b00c403f48d641 51e2287c3d1ee41b7e13769862add61dcd292a623cf943abc5968c984e246bcf
Sous-chef state: 8c0a9567e69f8c06dc908289a9e833a3e3c7913c6199d65b3edd43bcc9fdb3d5

Generated by 👨‍🍳 PR Sous Chef · pi · haiku45 · 4.51 AIC · ⌖ 7.85 AIC · ⊞ 1K · ◷
_{Comment /souschef to run again}

@copilot address the following outstanding work in one pass:

1. Update this branch with the latest main using make merge-main, resolving any conflicts and preserving the intended changes....

Pushed 6aef391 after merging the latest main and recompiling all 333 workflows. The Starlight fallback now shares the Antigravity description with social/JSON-LD metadata, with a regression test. The reported agent job failed on Codex invalid_request_body; conclusion failed as a consequence. Docs build/Playwright were blocked because the configured npm feed could not resolve (ENOTFOUND). The review thread has a reply but remains unresolved; the available GitHub integration does not expose thread resolution.