I wrote a first version of a howto about the creation of LibreOffice non-code extensions. This howto is written in German language and the source code is available from my Github repository:
https://github.com/andreasma/extensionbook
I added some sample templates to this repository, one for each LibreOffice non-code extension, which I described in the howto. You could view them here:
https://github.com/andreasma/extensionbook/tree/master/extensiontemplates
You could check out this code samples and adapt (by editing) them to your own new LibreOffice non-code extension.
I’m keen to see your LibreOffice non-code extension inside the LibreOffice extension repository: https://extensions.libreoffice.org
Happy hacking!