fix: UI overhaul — align all HTMX views with Lumina Design System (46 fixes)

- All 7 pages rewritten: Dashboard, Terminal, Snippets, Keychain, SFTP, Settings, Brief
- Apply consistent Lumina glassmorphic theme (rounded-2xl, shadows, borders, tracking)
- Fix SVG icons not rendering — return template.HTML instead of string
- Fix Alpine x-data scoping: terminal tabs, SFTP modals, snippet tag buttons
- Fix dashboard search sending literal ?q=...
- Rebuild CSS with all new Tailwind classes (62KB)
- Add .air.toml with hot-reload config, docs/PERBAIKANUI.md checklist
- Remove unused backup partials

app/backend/internal/handler/settings.go

@@ -10,13 +10,17 @@ var deviceStore = model.NewDeviceStore()
 var settingsStore = store.NewSettingsStore()
 
 func Settings(c *fiber.Ctx) error {
-	return c.Render("settings", fiber.Map{
+	data := fiber.Map{
 		"View":      "settings",
 		"Title":     "Settings",
 		"Config":    settingsStore.Get(),
 		"Devices":   deviceStore.All(),
 		"NavItems":  navItems,
-	})
+	}
+	if c.Get("HX-Request") != "" {
+		return c.Render("settings_content", data)
+	}
+	return c.Render("settings", data)
 }
 
 func UpdateConfig(c *fiber.Ctx) error {