feat: add option to run tinyauth on a top-level domain (#710)

* Add TINYAUTH_AUTH_SUBDOMAINSENABLED option

Setting it to false allows to use Tinyauth on top-level domain only,
but forbids automatic cross-app authentication using Traefik/Nginx.

* fix: inform services and controllers if subdomain cookie domain is enabled

* chore: rabbit feedback

* fix: deny ip addresses for standalone domain

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Co-authored-by: Stavros <steveiliop56@gmail.com>

internal/bootstrap/router_bootstrap.go

@@ -84,6 +84,7 @@ func (app *BootstrapApp) setupRouter() (*gin.Engine, error) {
 		RedirectCookieName:     app.context.redirectCookieName,
 		CookieDomain:           app.context.cookieDomain,
 		OAuthSessionCookieName: app.context.oauthSessionCookieName,
+		SubdomainsEnabled:      app.config.Auth.SubdomainsEnabled,
 	}, apiRouter, app.services.authService)
 
 	oauthController.SetupRoutes()