New synced gearset default filtering improvements

[jtcasper]

Describe the bug
When creating a new lvl 100, i735 set (for FRU for example) 0 pieces of LHW, Clouddark, or in 7.3 dungeon gear are displayed by default.

I believe this also impacts unreal sets, fwiw.

Expected behavior
It may be straightforward enough that when a sheet is created with a specific ilvl sync, that gear starting at that ilvl or 5 ilvls below maybe should be the lower bound of the filter. I believe level 70, 80, 90 sets already do this.