PR created by the Librarian CLI to initialize a release. Merging this PR
will auto trigger a release.

Librarian Version: v1.0.1
Language Image:
us-central1-docker.pkg.dev/cloud-sdk-librarian-prod/images-prod/python-librarian-generator@sha256:b8058df4c45e9a6e07f6b4d65b458d0d059241dd34c814f151c8bf6b89211209
<details><summary>google-auth: 2.46.0</summary>

##
[2.46.0](v2.45.0...v2.46.0)
(2026-01-05)

### Features

* Recognize workload certificate config in
has_default_client_cert_source for mTLS for Agentic Identities (#1907)
([0b9107d](0b9107d5))

### Bug Fixes

* Fix test coverage for mtls_helper (#1886)
([02e7163](02e71631))

* use .read() instead of .content.read() in aiohttp transport (#1899)
([12f4470](12f4470f))

* add types to default and verify_token and Request __init__ based on
comments in the source code. (#1588)
([59a5f58](59a5f588))

* fix the document of secure_authorized_session (#1536)
([5d00147](5d001470))

* raise RefreshError for missing token in impersonated credentials
(#1897)
([94d04e0](94d04e09))

* remove setup.cfg configuration for creating universal wheels (#1693)
([c767531](c767531c))

### Documentation

* update urllib3 docstrings for v2 compatibility (#1903)
([3f1aeea](3f1aeea2))

</details>