Move logic for generating uniques into export scripts

[sida-wang]

Description of the problem being solved:

Currently generated uniques are being processed on startup. This PR shifts the generation into the export scripts which will provide more transparency on what data PoB is reading in for these uniques.

Most of the logic from the shifted over from the existing Generated.lua with refactors where appropriate. A large part of the refactoring is shifting the extraction of mods for the uniques to be extracted from dat files rather than using Data.lua during runtime.

To-do:

• [x] Test and compare with existing implementation
• [x] Check if loadStatFile() should use a specific file L11. stat_descriptions.txt is sufficient for the mods on generated uniques.

Steps taken to verify a working solution:

• Compared number of variants for each generated unique - differences outlined in notes below
• Confirmed variant selection behaviour for each generated unique is appropriate

Notes

• Forbidden Shako and Replica Forbidden Shako variants reduced by 2 due to Elemental Penetration not being an indexable support gem.
• Skin of the Lords and Impossible Escape variants have reduced by 2 with the removal of Doomsday and Supreme Decadence (this should have been included in the exclusion list).