Bluespice Mediawiki
Extension of Mediawiki https://bluespice.com/products/features/
Community edition offers SAML auth.
Coding https://en.wiki.bluespice.com/wiki/How_to_become_a_BlueSpice_hacker
Code is at https://gerrit.wikimedia.org Wikimedia tech account needed)
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information