fix resolutions for items so mipmap level isnt lowered

[Boy0000]

18x18 and 18x36 is not divisible by 4, so the mipmap level is lowered causing blurry textures
this just rescales them to 16x16 and 16x32 to fix this

[14:59:38] [Worker-Main-84/WARN]:
Texture openinv:item/not_a_slot with size 18x18 limits mip level from 4 to 1
[19:24:32] [Worker-Main-106/WARN]:
Texture openinv:item/crafting_output with size 18x36 limits mip level from 4 to 1

[Jikoo]

Ah, things I don't experience as a serial low detail user, whoops. The multiples of 18 were important to line up with existing inventories when stretched out. Will this work out the same? Do we need to adjust the render size or should we consider doubling the pixel counts to 36x36/36x72 so they have a multiple of 4 and render the same way they currently do?
/e: I guess that doesn't matter for the blank slot, but the crafting arrow one could be messy.

Sorry if the questions are silly, I'm afraid I'm horribly inexperienced with resource packs and this all was kludged together by combing over the wiki and making mistakes for hours on end.

[Boy0000]

Sorry for the late response, it seems to remain just fine when testing it locally
the crafting slot is abit wack due to the pixel change but normal one is fine

after:

before:

[Boy0000]

pushed a fix that adjusts the output texture abit

[Jikoo]

Awesome, thank you!

An aside: I see you're using a custom pack that removes the inventory name, You should be able to set openinv.container.inventory.suffix="Inventory - %s" in the language file to replace the missing identifier if you want it.