Bring over the TUI to interactive installer (#845)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

internal/agent/TUIuserdataPage.go

@@ -0,0 +1,50 @@
+package agent
+
+import (
+	tea "github.com/charmbracelet/bubbletea"
+)
+
+// Userdata Page
+
+type userdataPage struct{}
+
+func (p *userdataPage) Title() string {
+	return "Userdata Generated"
+}
+
+func (p *userdataPage) Help() string {
+	return "Press any key to return to the summary page."
+}
+
+func (p *userdataPage) ID() string {
+	return "userdata"
+}
+
+func newUserdataPage() *userdataPage {
+	return &userdataPage{}
+}
+
+func (p *userdataPage) Init() tea.Cmd {
+	return nil
+}
+
+func (p *userdataPage) Update(msg tea.Msg) (Page, tea.Cmd) {
+	switch msg.(type) {
+	case tea.KeyMsg:
+		// Go back to customization page
+		return p, func() tea.Msg { return GoToPageMsg{PageID: "summary"} }
+	}
+	return p, nil
+}
+
+func (p *userdataPage) View() string {
+	s := "Userdata Generated (plain text):\n"
+	cc := NewInteractiveInstallConfig(&mainModel)
+	ccString, err := cc.String()
+	if err == nil {
+		s += "\n" + string(ccString) + "\n"
+	} else {
+		s += " (error displaying cloud config)\n"
+	}
+	return s
+}