Give the module an importable path

The module was declared as `module game`, which is not a resolvable
import path: nothing outside this repository could depend on the
konstructor engine, whatever it was published as. It is now
git.teletypegames.org/engines/gorpg, matching where the repo lives.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

main.go

@@ -1,9 +1,9 @@
 package main
 
 import (
-	"game/src/domain"
-	"game/src/konstructor"
-	"game/src/konstructor/engines/easy_ebitengine"
+	"git.teletypegames.org/engines/gorpg/src/domain"
+	"git.teletypegames.org/engines/gorpg/src/konstructor"
+	"git.teletypegames.org/engines/gorpg/src/konstructor/engines/easy_ebitengine"
 )
 
 func main() {