I want to make the functionality of a custom extension available via a menu item in the CKAN\'s main navigation menu. Not sure how I can add this new menu item from my extension
The CKAN Pages extension (for CKAN 2.2+) allows the addition of basic pages to CKAN, including the addition of appropriate links to the main menu. Admin users can configure the order of the pages within the menu and use CKAN's preferred Markdown language to set the content of the pages. In essence, it makes CKAN into a basic CMS.
More information: https://github.com/ckan/ckanext-pages
The extension is an official extension originally coined by the OKNF (makers of CKAN), so it's well done and (currently) well supported.