R1:38ae81fb3916

Throw when callers pass an invalid constraint to a "*.search" method

Summary:
Ref T11593. When you call a `*.search` method like `maniphest.search`, we don't currently validate that all the constraints you pass are recognized.

I think there were two very weak arguments for not doing this:

- It makes compatibility in `arc` across versions slightly easier: if we add a new constraint, we could add it to `arc` but also do client-side filtering for a while.
- Conduit parameter types //could//, in theory…