Until a fey mood goes amiss, and you're not around when that happens. Or when someone dies of old age. Though these things might not happen if you're playing with Elves (no modding expert), ofcourse.
Other than a fey mood failure, you should be able to rig the entire place with waterfalls to ensure maximum happiness, though there's the issue of powering all of those. Reactors would work, but then you're pretty much cheating/exploiting to activate the cheat. Enabling Pump Operating on everyone might do the trick for that.
Maybe.... if you reach that Booze Singularity Point, then make sure it's maintainable by a small amount of elves, you could murder every unneccesary inhabitant and make sure the survivors are all of the same sex, and have all mooded before.
That still leaves the issue of having to export the cloth. That means checking in with it at least once a year, but it also means you can't just wall it off. You'd also have to make absolutely sure nothing can go amiss when you open up for the traders, because a small mistake around year 99 could be catastrophical.
Mid-post reply:
I figured people would try that logic, which is why I also added:
All but 5 points must be spent on rope reed.
Meaning embark points. Good luck with that.
Hmm, that doesn't quite save your point, though. Processing rope reed always returns one or more seeds, meaning you'll always be able to create at least the same amount. Taking the arbitrary growth rate of 1 + 1 * 10^-200 would ensure you'd never have to export any more, and with the never-decreasing amount of seeds, this will meet the requirements.