I also accidentally hid this panel just now. I managed to get it back like this:

• Close CodeLite
• Open: C:\Users\your_username\AppData\Roaming\codelite\config\codelite.conf
• Find the line "ShowMenuBar"
• If the value "false" follows, then replace it with "true"
• Save and run CodeLite

After these actions, I got the main menu again