chore: release v1.19.6 - UI nav auth, SMTP UI-only, test messages, directory.md

### Fixed
- **Navbar shows Catalog/Vault for unauthenticated users** — Changed nav
  gating from `groups: []` (always visible) to `groups: ['login']` and
  added synthetic 'login' group handling in app-base.js.
- **500 ENOENT: no such file or directory, open '/docs/directory.md'** —
  Created the missing documentation file.

### Changed
- **SMTP configuration UI-only** — Removed SMTP from static config files
  (conf/base.js, sso-secrets.js, setup.env.example). SMTP is now only
  configurable via the runtime UI at /conf.

### Added
- **Test email/SMS capability** — Added POST /api/conf/test-email and
  POST /api/conf/test-sms endpoints with UI buttons in the Configuration
  page. Saves config first, then sends test message to verify settings.

### theta-env setup.sh
- **Non-interactive theta-agent configuration** — Added CFG_THETA_AGENT_ENABLE,
  CFG_THETA_AGENT_LDAP_AUTH, and CFG_THETA_AGENT_FULL_CONTROL variables to
  setup.env (all default to 1/enabled).

Co-Authored-By: Claude <noreply@anthropic.com>

nodejs/public/lib/js/app-base.js

@@ -615,9 +615,10 @@ app.util = (function(app){
 // Reveal every .group-required-<cn> element the current user's groups entitle
 // them to. Elements carrying .group-required start hidden (styles.css), so a
 // user who is in no groups — or who isn't logged in — simply never sees them.
+// The synthetic 'login' group is special: it's true for any authenticated user.
 app.auth.applyGroupVisibility = function(user){
 	var groups = app.auth.groupCNs(user);
-	if(!groups.length) return;
+	var isLoggedIn = !!user;
 
 	var style = document.getElementById('group-required-rules');
 	if(!style){
@@ -636,6 +637,19 @@ app.auth.applyGroupVisibility = function(user){
 			// A group whose CN isn't a usable CSS identifier just gates nothing.
 		}
 	}
+
+	// The 'login' group is synthetic — it means "any authenticated user".
+	// Reveal .group-required-login for any logged-in user.
+	if(isLoggedIn){
+		try{
+			style.sheet.insertRule(
+				`.group-required-login { display: revert !important; }`,
+				style.sheet.cssRules.length
+			);
+		}catch(error){
+			// Ignore CSS escape errors.
+		}
+	}
 };
 
 $( document ).ready(async function(){