revert pdsAgent commits & remove custom AppView support
Bye bye "fix: ensure `com.atproto.*` calls go through without proxying" "add deer custom-appview" "unproxy preferences" (ALSO removes the pdsAgent import added in "couple code error fixes" 3814f6b)
This reverts commits 69cf6f93b829d1d25e5fa37875d90070f68ef2ed, 6b305f2626cffa73b1989dec44a071ae7b4ba2b9, and 45584b9c28a5b657e3684b2d8f3cbea06668c116.