#3500071: Adding code components to components

• New button above the Preview panel in the code editor
  • Only appears when the code component is internal — Note: due to a backend bug, the auto-save endpoint always returns false
• New action for the listed components under Code in the left sidebar
• New dialog to confirm the action, update the code component, and navigate to /editor
  • The dialogs currently need a CodeComponentSerialized, so a new selector was added in codeEditorSlice to help with that — Note: this could be removed and a simplified type could be used for all dialogs when #3508140: PATCH request for config entities reset values that are not sent lands
• Filtered list under Code in the left sidebar to list only internal components