Core: Add settings API ("auto settings") for host.yaml (#1871)

* Add settings API ("auto settings") for host.yaml

* settings: no BOM when saving

* settings: fix saving / groups resetting themselves

* settings: fix AutoWorldRegister import

Co-authored-by: el-u <109771707+el-u@users.noreply.github.com>

* Lufia2: settings: clean up imports

* settings: more consistent class naming

* Docs: update world api for settings api refactor

* settings: fix access from World instance

* settings: update migration timeline

* Docs: Apply suggestions from code review

Co-authored-by: Zach Parks <zach@alliware.com>

* Settings: correctly resolve .exe in UserPath and LocalPath

---------

Co-authored-by: el-u <109771707+el-u@users.noreply.github.com>
Co-authored-by: Zach Parks <zach@alliware.com>

worlds/dkc3/__init__.py

@@ -3,6 +3,7 @@ import typing
 import math
 import threading
 
+import settings
 from BaseClasses import Item, MultiWorld, Tutorial, ItemClassification
 from .Items import DKC3Item, ItemData, item_table, inventory_table, junk_table
 from .Locations import DKC3Location, all_locations, setup_locations
@@ -17,6 +18,16 @@ from .Rom import LocalRom, patch_rom, get_base_rom_path, DKC3DeltaPatch
 import Patch
 
 
+class DK3Settings(settings.Group):
+    class RomFile(settings.UserFilePath):
+        """File name of the DKC3 US rom"""
+        copy_to = "Donkey Kong Country 3 - Dixie Kong's Double Trouble! (USA) (En,Fr).sfc"
+        description = "DKC3 (US) ROM File"
+        md5s = [DKC3DeltaPatch.hash]
+
+    rom_file: RomFile = RomFile(RomFile.copy_to)
+
+
 class DKC3Web(WebWorld):
     theme = "jungle"
 
@@ -40,6 +51,7 @@ class DKC3World(World):
     """
     game: str = "Donkey Kong Country 3"
     option_definitions = dkc3_options
+    settings: typing.ClassVar[DK3Settings]
     topology_present = False
     data_version = 2
     #hint_blacklist = {LocationName.rocket_rush_flag}