Fix link title fallback in ToC item

[clairechabas]

We need to account for the linkTitle being an empty string.

[changeset-bot]

⚠️ No Changeset found

Latest commit: f33799b

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[github-actions]

Summary of the deployments:

Version	URL	Status
Vercel	https://gitbook-v2-4qn7xyonr-gitbook.vercel.app	✅
Cloudflare	https://68ed268a-gitbook-open-v2-preview.gitbook.workers.dev	✅

Test content

Site	2v	2c
GitBook	https://gitbook-v2-4qn7xyonr-gitbook.vercel.app/url/gitbook.com/docs	https://68ed268a-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.com/docs
E2E	https://gitbook-v2-4qn7xyonr-gitbook.vercel.app/url/gitbook.gitbook.io/test-gitbook-open	https://68ed268a-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.gitbook.io/test-gitbook-open

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Build	Status	Details	Updated (UTC)
customers-v2 (Inspect)	✅ No changes detected	-	Dec 4, 2025, 11:40 AM
v2-cloudflare (Inspect)	👍 Changes approved	9 changed	Dec 4, 2025, 11:44 AM
v2-vercel (Inspect)	👍 Changes approved	14 changed	Dec 4, 2025, 11:44 AM

[conico974]

You missed the one in packages/gitbook/src/lib/references.tsx