The previous commit added five direct clients (Douyin, Microsoft, Facebook,
Twitter, Apple) written against each platform's own endpoints. Maintaining
five bespoke OAuth implementations — including Apple's ES256 client secret and
Twitter's PKCE — is maintenance the bundled yurunsoft SDK does not ask for,
and none of them could be verified without production credentials.
Only providers yurunsoft/yurun-oauth-login actually implements stay on the
direct surface: GitHub, Gitee, QQ, Google, Weibo, Weixin, Baidu and Alipay.
Baidu and Alipay move into OAuthProviderBroker's existing client() switch and
normalize() map rather than living in a separate class, so there is no new
layer to reason about.
OAuthProviderClient, its harness and its contract test are deleted outright
(-809 lines). The Apple form_post handling added to handle_callback() is
reverted too — without Apple there is no POST callback to read.
The aggregate-login channel keeps its 16 platforms, matching the reference;
that list describes what the aggregation provider offers, not a local
implementation. Brand icons for those names stay for the same reason.
Verification: 869 widget/navigation tests pass, the PSR-4 audit reports 0
errors, and the catalog constant, PHP schema and Vue schema now list the same
16 aggregate platforms.