fix: Standardize slugifying collection and org name

[SuaYoo]

Resolves #3351

Changes

• Fixes frontend and backend using different methods to slugify name by passing in slug from frontend
• Fixes slug max length to match backend max length
• Validates slug on frontend
• Documents collection name and summary in user guide

Manual testing

Regression test that the following will update the slug to expected value:

• Create new org from superadmin dashboard
• Create new collection from "Create a New Collection" dialog
• Create new collection from workflow "Deduplication" section
• Edit collection name from "Collection Settings" dialog

[tw4l]

Nice! Tested locally, working well