feat(auth): pass callback url through login

[altaywtf]

Summary

Adds a callbackUrl option to auth.login and serializes it as callback_url for the credential login endpoint.

Changed

• Adds a public LoginInput type for the auth login surface
• Reuses that type in the Promise client
• Sends callback_url through the existing query builder
• Updates request-shape coverage and README usage

Risks

Low. Existing login calls keep the same required fields and the new field is optional. Current backend behavior accepts the query parameter but does not enforce callback behavior yet, so server-side callback validation remains a backend follow-up.

Verification

• vp run verify
• git diff --check
• focused live probe confirmed login requests with callback_url are accepted and resulting tokens validate
• autoreview --mode branch --base origin/main clean

Complexity

Neutral. This narrows duplicate inline typing by sharing the public login input type.

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Summary by cubic

Add optional callbackUrl to auth.login, sent as callback_url in the login request. Introduces a public LoginInput type used by the Promise client, with tests and README updated.

^{Written for commit e33b8c3. Summary will update on new commits.}

[Copilot]

Pull request overview

Adds an optional callbackUrl to the auth.login API surface and forwards it to the credentials login endpoint as the callback_url query parameter, while reducing duplicated inline typing by introducing a shared public input type.

Changes:

• Introduces LoginInput as a public type for auth.login.
• Updates auth.login to serialize callbackUrl as callback_url in the request query.
• Reuses LoginInput in the Promise client and updates request-shape test + README usage.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
src/domains/auth.ts	Adds LoginInput and forwards callbackUrl as callback_url in login query params.
src/domains/auth.spec.ts	Updates auth flow coverage to assert callback_url is included/encoded in the login request URL.
src/core/client.ts	Reuses the shared LoginInput type for the Promise client auth.login signature.
README.md	Updates login usage example to include the optional callbackUrl field.

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[cubic-dev-ai]

No issues found across 4 files

_{Re-trigger cubic}

[putio-release-bot]

🎉 This PR is included in version 9.4.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀