chore: add contract-contract interation with ownership example

gno.land/cmd/gnoland/testdata/grc20-registry.txtar

@@ -0,0 +1,61 @@
+# test for add package
+
+## start a new node
+gnoland start
+
+# add registry
+gnokey maketx addpkg -pkgdir $WORK/registry -pkgpath gno.land/r/registry -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1
+
+# we call Transfer with foo20, before it's registered
+gnokey maketx call -pkgpath gno.land/r/registry -func TransferByName -args 'foo20' -args 'g123456789' -args '42' -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1
+stdout 'not found'
+
+# add foo20, and foo20wrapper
+gnokey maketx addpkg -pkgdir $WORK/foo20 -pkgpath gno.land/r/foo20 -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1
+gnokey maketx addpkg -pkgdir $WORK/foo20wrapper -pkgpath gno.land/r/foo20wrapper -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1
+
+# we call Transfer with foo20, after it's registered
+gnokey maketx call -pkgpath gno.land/r/registry -func TransferByName -args 'foo20' -args 'g123456789' -args '42' -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1
+stdout 'same address, success!'
+
+-- registry/registry.gno --
+package registry
+
+import "std"
+
+type transferCb func(to std.Address, amount uint64) string
+type pair struct {name string; cb transferCb}
+var registry = []pair{}
+func Register(name string, cb transferCb) { registry = append(registry, pair{name: name, cb: cb}) }
+func TransferByName(name string, to string, amount uint64) string {
+	for _, pair := range registry {
+		if pair.name ==  name {
+			if std.CurrentRealm().Addr().String() == pair.cb(std.Address(to), amount) {
+				return "same address, success!"
+			} else {
+				return "invalid address, ownership issue :("
+			}
+		}
+	}
+	return "not found"
+}
+
+-- foo20wrapper/foo20wrapper.gno --
+package foo20wrapper
+
+import "gno.land/r/registry"
+import "gno.land/r/foo20"
+
+func init() {
+	  registry.Register("foo20", foo20.Transfer)	
+}
+
+-- foo20/foo20.gno --
+package foo20
+
+import "std"
+
+func Transfer(to std.Address, amount uint64) string {
+	println("transfer from=" + std.PrevRealm().Addr().String() + " to=" + to.String() + " some-amount")
+	return std.PrevRealm().Addr().String()
+}