fix(types): OAuthError.inner, saveToken input, and getClient clientSecret

[dhensby]

What

Three index.d.ts typing corrections.

Closes #367. Closes #368.

Changes

fix(types): add missing OAuthError.inner property (#367)

OAuthError sets this.inner to the wrapped error when constructed from another Error (oauth-error.js), and the handlers do exactly that (new ServerError(e)), but the property was missing from the published typings. Added inner?: Error. Thanks @papermana for the report.

Note: @wille suggested exposing the wrapped error via the standard Error.cause instead. That's a good idea, but it's a runtime change — this PR just documents the property that already exists. Adopting .cause (keeping .inner as a deprecated alias) would be a sensible follow-up.

fix(types): correct saveToken input to exclude client/user (#368)

The grant types call model.saveToken() with a token object that does not include client/user — they're passed as separate arguments and must be present on the returned value (TokenModel requires them). Typing the input as the full Token let saveToken(token) { return token } type-check while throwing at runtime. Narrowed the input to Omit<Token, 'client' | 'user'>. Thanks @papermana.

fix(types): allow getClient clientSecret to be omitted

The token handler calls model.getClient() with no client secret for public / PKCE clients (clientSecret is undefined), and the docs describe it as nullable, but the typing required a string. Made it optional (clientSecret?: string). This addresses the secondary typing point raised by @Valerionn in #281's thread.

Notes

• Verified index.d.ts still compiles cleanly (tsc --noEmit --strict).
• The saveToken change is a type-only tightening: it can surface (correct) compile errors in consumer code that relied on the old, inaccurate type. No runtime change — but you may prefer to release it in a minor rather than a patch.

🤖 Generated with Claude Code

[jankapunkt]

Due to the recommendation of a minor release I am about to create an RC for this. Any objections @dhensby ?

[dhensby]

Due to the recommendation of a minor release I am about to create an RC for this. Any objections @dhensby ?

Maybe wait for a few more PRs to land 😉