example: add fork targets

example/4788asm.eas

@@ -22,6 +22,7 @@
 ;;; buflen to the timestamp's index in the first ring buffer. The sum will be
 ;;; the storage slot in the second ring buffer where it is stored.
 
+#pragma fork "cancun"
 
 ;;; -----------------------------------------------------------------------------
 ;;; MACROS ----------------------------------------------------------------------

example/4788asm_ctor.eas

@@ -5,7 +5,9 @@
 ;;;   /_/  /_/\____/\____/\__,_/____/_/ /_/ /_/
 ;;;
 ;;; constructor code
-
+
+#pragma fork "cancun"
+
     push @.end - @.start  ; [size]
     dup1                  ; [size, size] 
     push @.start          ; [start, size, size]

example/erc20/erc20.eas

@@ -7,6 +7,8 @@
 ;;; balance(address)          => 0x000000000000000000000000 || address
 ;;; allowance(owner, spender) => keccak(owner || spender)
 
+#pragma fork "constantinople"
+
 #define %match(candidate, label) { ; [selector]
     dup1             ; [selector, selector]
     push $candidate  ; [candidate, selector, selector]

example/erc20/erc20_ctor.eas

@@ -1,6 +1,8 @@
 ;;; ERC20 - constructor
 ;;;
 
+#pragma fork "constantinople"
+
     pc                  ; [0]
 
     ;; give deployer initial supply