Update terminology used in the webapp

[SovereignAndrey]

• Charity vs Endowment vs Normal Endowment vs AIF vs AST.
• No matter the type of endowment that's trying to access the Admin dashboard, we refer to its role (or type on RC-v1.8) as "charity". The page for the admin dashboard for all endowments is named Charity.tsx even for non-charity (normal) endowments.
• Even small misalignments like Favorite vs Bookmark

The terminology used in the webapp is getting more and more misaligned from the terminology we use in our discussions, causing unnecessary mental "context switches". This drains just a tiny bit of mental energy, but it can add up. Also increases the chance to use wrong types in wrong places ("AIFs should have their own admin pages. (later) Oh, AIF is just a different name for 'normal endowment', need to revert the change" OR "Need to update this AST name - where the hell is the AST page or Figma design??").

Also increases time for newcomers to get comfortable with the codebase and this even applies to current devs who do not yet understand certain terms and how they apply to the current codebase.