add options file for library-wide configuration

_CoqProject

@@ -5,6 +5,7 @@
 # (https://github.com/coq/coq/issues/6294).
 -arg -w -arg -redundant-canonical-projection
 
+theories/options.v
 theories/algebra/monoid.v
 theories/algebra/cmra.v
 theories/algebra/big_op.v

theories/options.v

+(** Coq configuration for Iris (not meant to leak to clients) *)
+(* Everything here should be [Export Set], which means when this
+file is *imported*, the option will only apply on the import site
+but not transitively. *)
+Export Set Default Proof Using "Type".