Support Gitea

### Description

Please consider support for Gitea accounts, in addition to Github and Gitlab

see [https://about.gitea.com]

### Alternatives Considered

N/A

### Additional Context

Many people are now using Gitea, a self-hosted platform. Adding support would make developers' lives easier. Tkank you.

### Screenshots

_No response_

Start by locating the existing GitHub and GitLab account-support entry points and comparing how those integrations are structured. The issue does not identify files, tests, or expected behavior, so first clarify the Gitea account flows and define what complete support includes before implementation.

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