Turn on the "noUncheckedIndexedAccess" flag in all TS config files

[utkuufuk]

noUncheckedIndexedAccess flag ensures that accessing elements in arrays or objects doesn't result in undefined or null, preventing a certain class of runtime errors. Without it, developers might overlook potential null or undefined values, leading to unexpected behaviors.

I "properly" fixed existing errors that were obvious and easy to fix. I used ! or the @ts-expect-error directive for others to avoid spending too much time on this.

The main idea is to avoid creating more problems in the future as the compiler will now start warning us.

[changeset-bot]

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Latest commit: 4a5f1cb

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[github-actions]

Summary of the deployments:

Version	URL	Status
Vercel	https://gitbook-v2-p9ckp1dyw-gitbook.vercel.app	✅
Cloudflare	https://1de010d2-gitbook-open-v2-preview.gitbook.workers.dev	✅

Test content

Site	2v	2c
GitBook	https://gitbook-v2-p9ckp1dyw-gitbook.vercel.app/url/gitbook.com/docs	https://1de010d2-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.com/docs
E2E	https://gitbook-v2-p9ckp1dyw-gitbook.vercel.app/url/gitbook.gitbook.io/test-gitbook-open	https://1de010d2-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)	👍 Changes approved	2 changed	Aug 26, 2025, 4:17 PM
v2-cloudflare (Inspect)	✅ No changes detected	-	Aug 26, 2025, 4:25 PM
v2-vercel (Inspect)	👍 Changes approved	1 changed	Aug 26, 2025, 4:19 PM