feat: Improve oauth redirect (#303)

* fix: redirects after oauth can potentially misalign with server's actually hostname

* feat: remove `RedirectURL` from oauth config, as it should checked by provider rather than client

* feat: align oauth endpoint with the hostname in requests

http/request/admin/oauth.go

@@ -22,7 +22,6 @@ type OauthForm struct {
 	Scopes       string `json:"scopes" validate:"omitempty"`
 	ClientId     string `json:"client_id" validate:"required"`
 	ClientSecret string `json:"client_secret" validate:"required"`
-	RedirectUrl  string `json:"redirect_url" validate:"required"`
 	AutoRegister *bool  `json:"auto_register"`
 	PkceEnable   *bool  `json:"pkce_enable"`
 	PkceMethod   string `json:"pkce_method"`
@@ -34,7 +33,6 @@ func (of *OauthForm) ToOauth() *model.Oauth {
 		OauthType:    of.OauthType,
 		ClientId:     of.ClientId,
 		ClientSecret: of.ClientSecret,
-		RedirectUrl:  of.RedirectUrl,
 		AutoRegister: of.AutoRegister,
 		Issuer:       of.Issuer,
 		Scopes:       of.Scopes,