chore: rework layout primitives

packages/tui/internal/components/chat/editor.go

@@ -22,7 +22,7 @@ import (
 type EditorComponent interface {
 	tea.Model
 	tea.ViewModel
-	layout.Sizeable
+	SetSize(width, height int) tea.Cmd
 	Content() string
 	Lines() int
 	Value() string
@@ -158,7 +158,15 @@ func (m *editorComponent) Content() string {
 
 func (m *editorComponent) View() string {
 	if m.Lines() > 1 {
-		return ""
+		t := theme.CurrentTheme()
+		return lipgloss.Place(
+			m.width,
+			m.height,
+			lipgloss.Center,
+			lipgloss.Center,
+			"",
+			styles.WhitespaceStyle(t.Background()),
+		)
 	}
 	return m.Content()
 }

packages/tui/internal/components/chat/messages.go

@@ -21,6 +21,7 @@ import (
 type MessagesComponent interface {
 	tea.Model
 	tea.ViewModel
+	SetSize(width, height int) tea.Cmd
 	PageUp() (tea.Model, tea.Cmd)
 	PageDown() (tea.Model, tea.Cmd)
 	HalfPageUp() (tea.Model, tea.Cmd)
@@ -311,6 +312,7 @@ func (m *messagesComponent) View() string {
 	if len(m.app.Messages) == 0 {
 		return m.home()
 	}
+	t := theme.CurrentTheme()
 	if m.rendering {
 		return lipgloss.Place(
 			m.width,
@@ -318,19 +320,18 @@ func (m *messagesComponent) View() string {
 			lipgloss.Center,
 			lipgloss.Center,
 			"Loading session...",
+			styles.WhitespaceStyle(t.Background()),
 		)
 	}
-	t := theme.CurrentTheme()
-	return lipgloss.JoinVertical(
-		lipgloss.Left,
-		lipgloss.PlaceHorizontal(
-			m.width,
-			lipgloss.Center,
-			m.header(),
-			styles.WhitespaceStyle(t.Background()),
-		),
-		m.viewport.View(),
+	header := lipgloss.PlaceHorizontal(
+		m.width,
+		lipgloss.Center,
+		m.header(),
+		styles.WhitespaceStyle(t.Background()),
 	)
+	return styles.NewStyle().
+		Background(t.Background()).
+		Render(header + "\n" + m.viewport.View())
 }
 
 func (m *messagesComponent) home() string {