Updates/fixes to selectedMessage handling in chat TUI view

pkg/tui/views/chat/input.go

@@ -53,6 +53,13 @@ func (m *Model) handleInput(msg tea.KeyMsg) tea.Cmd {
 		return shared.KeyHandled(msg)
 	case "ctrl+t":
 		m.showDetails = !m.showDetails
+		if !m.showDetails && m.selectedMessage == 0 {
+			if len(m.App.Messages) > 1 {
+				m.selectedMessage = 1
+			} else {
+				m.selectedMessage = -1
+			}
+		}
 		m.rebuildMessageCache()
 		m.updateContent()
 		return shared.KeyHandled(msg)
@@ -157,6 +164,9 @@ func (m *Model) handleInputKey(msg tea.KeyMsg) tea.Cmd {
 			}
 			offset := m.messageOffsets[m.selectedMessage]
 			tuiutil.ScrollIntoView(&m.content, offset, m.content.Height/2)
+		} else {
+			m.selectedMessage = -1
+			m.content.GotoTop()
 		}
 		m.updateContent()
 		m.input.Blur()