Minecraft – Mobs aren’t spawning in the Minecraft PE Server

Well, first of all dark room mob spawners aren't very effective unless put to a large scale. I would suggest that you make a 30 by 30 platform which can have another platform 10 blocks above, it has to be nighttime and no other mobs are allowed to spawn around the building, also, you have to have holes in the floor with trapdoors, you can make the trapdoors activate at the hit of a lever. The reason why you want to use trapdoors that are open is because mob AI detect trapdoors as standing blocks whether they are open or closed, also, no water because of update with drowned. Also, its a good idea not to build on slime chunks, can decrease entity spawning. Lastly, one thing for you to check, do /kill @e to reset the entity spawning in area.

Because you accidentally attacked a villager or two, your popularity in the village is probably low enough that the Iron Golems will attack you on sight.

One option is to prevent more Iron Golems from spawning, and then killing any remaining ones aggressive towards you in the village. You should theoretically be able to prevent them from spawning by either reducing the village population to fewer than ten villagers, or by reducing the number of homes (a home can be removed by deleting the wooden door—the structure itself does not need to be demolished) to fewer than 21.

Once you have prevented the Golems from spawning, you can attempt to increase your popularity with the villagers, to prevent any golems that spawn in the future—because of population increase/home construction—from being hostile. The only way I know of to increase popularity with villagers is to trade with them, specifically for their last item (related Arqade question).

Another option, if you don't care about the village at all, is to wipe out the village's population, resetting your popularity for that village.

Disclaimer: I have not tried the aforementioned solutions myself, so I cannot guarantee they will work.