tui: Add setting view with support for changing the current model

pkg/tui/shared/shared.go

@@ -22,24 +22,24 @@ type View int
 const (
 	ViewChat View = iota
 	ViewConversations
-	//StateSettings
+	ViewSettings
 	//StateHelp
 )
 
 type (
 	// send to change the current state
 	MsgViewChange View
-	// sent to a state when it is entered
-	MsgViewEnter struct{}
+	// sent to a state when it is entered, with the view we're leaving
+	MsgViewEnter View
 	// sent when a recoverable error occurs (displayed to user)
 	MsgError struct { Err error }
 	// sent when the view has handled a key input
 	MsgKeyHandled tea.KeyMsg
 )
 
-func ViewEnter() tea.Cmd {
+func ViewEnter(from View) tea.Cmd {
 	return func() tea.Msg {
-		return MsgViewEnter{}
+		return MsgViewEnter(from)
 	}
 }