新增 OIDC/SSO、邮件验证码与 Gitea 项目同步，并强化 Feed 与管理后台。

作为 OIDC Provider 对接 Gitea；注册支持邮件验证码/验证码；侧栏同步公开仓库；Feed 分页、文章大纲、标签云与站点品牌设置。

Co-authored-by: Cursor <cursoragent@cursor.com>

embed_static/embed.go

@@ -53,7 +53,9 @@ func IsSPARoute(path string) bool {
 		strings.HasPrefix(path, "/admin") ||
 		strings.HasPrefix(path, "/uploads") ||
 		strings.HasPrefix(path, "/legacy") ||
-		strings.HasPrefix(path, "/assets") {
+		strings.HasPrefix(path, "/assets") ||
+		strings.HasPrefix(path, "/oauth") ||
+		strings.HasPrefix(path, "/.well-known") {
 		return false
 	}
 	return true