nas-samba v1.0.1: health check, hostname, remove demo credentials

- Add health check (curl /api/health) so Traefik can verify container health
- Set container hostname to nas.alexzaw.dev
- Remove hardcoded demo credentials from login page
- Remove admin123 fallback password — require SMB_PASSWORD env var
- Fail fast if no admin password is configured

apps/nas-samba/source/app/frontend/src/components/LoginPage.js

@@ -129,11 +129,7 @@ function LoginPage() {
 
           <div className="mt-8 p-4 bg-muted rounded-lg">
             <p className="text-sm text-muted-foreground">
-              <span className="font-medium text-foreground">Demo credentials:</span>
-              <br />
-              Username: <code className="font-mono bg-background px-1 rounded">admin</code>
-              <br />
-              Password: <code className="font-mono bg-background px-1 rounded">admin123</code>
+              Use your NAS credentials to sign in. Contact your administrator if you need access.
             </p>
           </div>
         </div>