build: client_library flag to build only used modules, remove package yaml (#1394)

* move dependencies to library

* remove package.yaml

* remove auto-generated comment

* cleanup target definitions

* add executable options

* add test rtsopts

* revert common options

* don't hide unused packages warning

* Add client_only cabal flag (#1396)

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Co-authored-by: IC Rainbow <aenor.realm@gmail.com>
Co-authored-by: Alexander Bondarenko <486682+dpwiz@users.noreply.github.com>

src/Simplex/FileTransfer/Client.hs

@@ -29,7 +29,6 @@ import qualified Data.X509.Validation as XV
 import qualified Network.HTTP.Types as N
 import qualified Network.HTTP2.Client as H
 import Simplex.FileTransfer.Protocol
-import Simplex.FileTransfer.Server.Env (supportedXFTPhandshakes)
 import Simplex.FileTransfer.Transport
 import Simplex.Messaging.Client
   ( NetworkConfig (..),