zuse: better ethereum abi data type

Considering some of the options here were atoms, not cells, $% wasn't
appropriate, and led to *etyp:abi:ethereum resulting in ford %ride execution
failure. Simply using $? instead would result in a fish-loop, so here we split
the atom cases from the tagged union ones with a $@.

pkg/arvo/sys/zuse.hoon

@@ -8171,15 +8171,18 @@
     =>  |%
         ::  solidity types. integer bitsizes ignored
         ++  etyp
-          $%  ::  static
+          $@  $?  ::  static
                   %address  %bool
                   %int      %uint
                   %real     %ureal
+                  ::  dynamic
+                  %bytes    %string
+              ==
+          $%  ::  static
               [%bytes-n n=@ud]
               ::  dynamic
               [%array-n t=etyp n=@ud]
               [%array t=etyp]
-              %bytes    %string
           ==
         ::
         ::  solidity-style typed data. integer bitsizes ignored