Support system as a default theme mode

[nolannbiron]

[WIP] Needs API update

[changeset-bot]

⚠️ No Changeset found

Latest commit: 34d70ee

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[github-actions]

Summary of the deployments:

Version	URL	Status
Vercel	https://gitbook-v2-ngar153d4-gitbook.vercel.app	✅
Cloudflare	https://e162972f-gitbook-open-v2-preview.gitbook.workers.dev	✅

Test content

Site	2v	2c
GitBook	https://gitbook-v2-ngar153d4-gitbook.vercel.app/url/gitbook.com/docs	https://e162972f-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.com/docs
E2E	https://gitbook-v2-ngar153d4-gitbook.vercel.app/url/gitbook.gitbook.io/test-gitbook-open	https://e162972f-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.gitbook.io/test-gitbook-open

[argos-ci]

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Build	Status	Details	Updated (UTC)
customers-v2-cloudflare (Inspect)	⚠️ Changes detected (Review)	26 changed	Mar 31, 2026, 3:58 PM
customers-v2-vercel (Inspect)	⚠️ Changes detected (Review)	26 changed	Mar 31, 2026, 3:57 PM
v2-cloudflare (Inspect)	⚠️ Changes detected (Review)	27 changed	Mar 31, 2026, 4:04 PM
v2-vercel (Inspect)	⚠️ Changes detected (Review)	30 changed	Mar 31, 2026, 4:03 PM