This concern is adressed in this paper: Getting it Right or Being Top Rank: Games in Citizen Science.
In a way, I think that a hard scientific publication (even in a supplementary material) remains the only way to openly and permanently recognise discoveries or inventors (outside of the commercial world with often "stolen" pattents).
This is a good question for citizen scientists however. Citizen scientists's contributions are standard recognised in "aknowledgments" in common scientific papers, often as a globality like "thanks to the numerous contributors …".
I think that Foldit does it well when including the actual foldit players in an authorship "consortium" "Foldit Players" with their real name in an annex, naming all contributors, with their aknowledgment, to a specific puzzle.
Other ways for co-authorship where tested in the past Foldit publications. One of them was to only name few players (the top scoring ones) as authors. But this proved to be unfair for all the players who did share recipes, functions of recipes, test solutions, discussions in the chat or in the wiki etc.
The authorship for the 100 000+ recipes is an interesting case: if one author invent a basic function (mainly when a new Lua Command appears), this function, or the idea of this function is then used by many chefs afterwards. Even the new command itself is often the response to a demand from the players in the forum. It's tricky to identify who actually participated to the idea of this improvement. Let'us give the authorship to the Foldit Researchers "with aknowledgment to the all Foldit Community".
Thus, "Foldit Players" is a minimum in order to aknowledge the all community of players. Then specificly aknowledging the players who actually participated in a specific puzzle is a good plus (this could be limited to those with more than one point per puzzle). Then, if relevant, specificly naming the players (or groups, then players of this group) who came with a specific solution that directly contributed to science is also nice, even if their results build on the all Foldit Community contributions, exactly like Scientists build not only on published papers but also on the all scientific community and other public facilities.
The way to aknowledge must however remain feasible at reasonable cost: for specific solutions, the Foldit Team has a track of the direct contributors, but no knowledge of the players who contributed with recipes or with ideas and shares in the group chat. Foldit team knows which players participated in a specific puzzle, but it would be almost impossible to trace the all real "coauthors" of the "winning" recipes used.
How to deal with the many many past players who some times added significant improvement in the game ? I still use strategies from pauldun, Mirp, tvdl, ravpnl, jean-bob, and I build on discussions with roukess in the chat during my first years playing.
Concerning strategies, I don't see other ways than supplementary materials (or real papers like I whrote with Marisa Ponti and collegues). The wiki is supposed to remain a free anonymous share to the World … and it can be used by AI which will steal his authorship …
This doensn't prevent us to specifically aknowledge here or in the wiki, famous contributors, like LociOiling, christoanchauvin, tvdl, rav_pnl (who whrote most of the functions we use in later recipes) or for exemple Auntdeen in the "memorials".