docs: document requireBaseUrl TypeScript generator config

[devin-ai-integration]

Summary

requireBaseUrl is a new opt-in TypeScript generator config flag that flips which client option is required: baseUrl becomes required and environment becomes optional. This matters for teams whose APIs have no named environments, or who want callers to point the SDK at an arbitrary host: previously those users still had to pass an environment string even though it wasn't a meaningful choice. With the flag on, baseUrl is the required, discoverable option, and generated snippets and the README construct the client the same way instead of showing a non-compiling environment example.

Implements docs for: feat(typescript): add requireBaseUrl config to require baseUrl and make environment optional (fern-api/fern#17321)

Docs changed

• fern/products/sdks/generators/typescript/configuration.mdx: adds a requireBaseUrl <ParamField> (boolean, default false) matching the shape of the neighboring options, covering the flipped required/optional client options, the snippet and README behavior, and that the option is ignored for APIs with multiple base URLs.

No SDK changelog entry, per the SDK changelog being handled separately.

Link to Devin session: https://app.devin.ai/sessions/1b65a5e95dfa4810bc5dc320e65ffc9d

[devin-ai-integration]

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[github-actions]

🌿 Preview your docs: https://fern-preview-devin-1785949647-ts-require-base-url.docs.buildwithfern.com/learn

Here are the markdown pages you've updated:

• learn/sdks/generators/typescript/configuration