Complete roadmap optionals: Holesail, Swarm UI, GitOps, virtualization.

Add tunnel persistence and container one-click tunnels with local
Holesail client bind, Swarm services/nodes/tasks view, GitOps stack
sync from git, deploy wizard step chrome, virtualized container lists,
and structure regression tests. Mark Tracks A–D and optional future done.

test/visual-structure.test.js

@@ -0,0 +1,54 @@
+/**
+ * Lightweight visual/structure regression: ensure critical UI landmarks stay in index.html.
+ * Complements full screenshot suites (optional future) without browser automation deps.
+ */
+import test from 'brittle'
+import fs from 'fs'
+import path from 'path'
+import { fileURLToPath } from 'url'
+
+const root = path.join(path.dirname(fileURLToPath(import.meta.url)), '..')
+const html = fs.readFileSync(path.join(root, 'index.html'), 'utf8')
+
+const REQUIRED_IDS = [
+  'sidebar',
+  'content',
+  'job-drawer',
+  'toast-stack',
+  'containers-view',
+  'deploy-view',
+  'tunnels-view',
+  'swarm-view',
+  'host-view',
+  'settings-view',
+  'deploy-wizard-steps',
+  'stack-git-url',
+  'tunnel-create-btn',
+  'swarm-services-body',
+]
+
+const REQUIRED_SNIPPETS = [
+  'data-view="tunnels"',
+  'data-view="swarm"',
+  'ENABLE_HOLESAIL',
+  'GitOps',
+  'collapse-sidebar-btn',
+]
+
+test('index.html retains critical view landmarks', (t) => {
+  for (const id of REQUIRED_IDS) {
+    t.ok(html.includes(`id="${id}"`), `missing #${id}`)
+  }
+})
+
+test('index.html retains critical feature snippets', (t) => {
+  for (const s of REQUIRED_SNIPPETS) {
+    t.ok(html.includes(s), `missing snippet: ${s}`)
+  }
+})
+
+test('modern.css includes collapsed sidebar rail rules', (t) => {
+  const css = fs.readFileSync(path.join(root, 'ui/modern.css'), 'utf8')
+  t.ok(css.includes('#sidebar.collapsed'))
+  t.ok(css.includes('icon') || css.includes('nav-link'))
+})