willchen96 won't let you share a matter with yourself

Across Mike's shared spaces - collaborative workflows, projects, and the tabular review tool - owners were able to "share" with their own address. It granted nothing new (owners already have full access), but it cluttered member lists and made access states harder to read at a glance. willchen96 closed the gap and, rather than patching one screen, enforced the same rule at every entry point: the system now refuses a self-share whether it's created through a project, an update, or a review, and the interface stops the request before it's even sent.

The same pass also tidied how share addresses are stored, trimming stray spacing and casing so the same collaborator can't show up twice under slightly different spellings. The result is one clean, predictable membership list per shared item.