SideContentTab.id should not be optional

[chownces]

The mobile workspace uses these IDs to track the currently selected tab, and renders the corresponding panel. Not specifying the ID would result in an empty panel being rendered.

src/commons/sideContent/SideContentTypes.ts

export type SideContentTab = {
  label: string;
  iconName: IconName;
  body: JSX.Element;
  toSpawn: (context: DebuggerContext) => boolean;
  id?: SideContentType;
  disabled?: boolean;
};

To also check if importing multiple modules would be affected, since they are all attached the SideContentType.module id, which is not unique (see SideContentHelper.ts)