feat: support issuerUri/jwkSetUri and multiple scopes for SSO OAuth2

[iLay1678]

1. 支持 issuerUri 和 jwkSetUri：新增了可选配置项，允许手动指定发行人标识符（Issuer Identifier）和 JWK Set URI。这在自动发现受限或需要特定端点时非常有用。
2. 支持多 Scope：允许 scopes 配置接受以空格或逗号分隔的多个值（例如 openid profile email 或 openid,profile,email），这些值将被正确解析并在授权请求中发送。

Fixes #79
Fixes #88

1. 自定义SSO支持 `issuerUri` 和 `jwkSetUri`
2. 自定义SSO支持多 Scope

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