✨ Add IntEnum for sqltypes

[KunxiSun]

I add a IntEnum type decorator which I used in my private project.

I wish it helps!

from enum import IntEnum
class HeroStatus(IntEnum):
    ACTIVE = 1
    DISABLE = 2    

from sqlmodel import IntEnum
class Hero(SQLModel):
    hero_status: HeroStatus = Field(sa_type=IntEnum(HeroStatus))


# Save as Integer in database, but load as IntEnum in program
user.hero_status == HeroStatus.ACTIVE      

[KunxiSun]

@KunxiSun: Yes - those are unrelated to your PR. We're looking into it here.

Thanks to let me know

[YuriiMotov]

@KunxiSun, thanks for your interest and efforts!

I think this feature is quite useful.
There seems to be no simple solution to configure int enums this way without creating custom TypeDecorator. This PR will provide such solution.

Please take a look at my in-code comments.
Also, we need to update these tests to check statements for new field

[YuriiMotov]

Suggested change

	if value is None:
	return None
	result = self.enum_type(value)
	return result
	return None if (value is None) else self.enum_type(value)

[YuriiMotov]

Suggested change

	if value is None:
	return None
	result = value.value
	return result
	return None if (value is None) else value.value

[YuriiMotov]

Suggested change

	class IntEnum(types.TypeDecorator): # type: ignore
	class IntEnum(types.TypeDecorator[Optional[_TIntEnum]]):

[YuriiMotov]

Suggested change

	def process_result_value( # type: ignore[override]
	def process_result_value(

[YuriiMotov]

Suggested change

	from enum import IntEnum as _IntEnum
	import enum

[YuriiMotov]

Suggested change

	_TIntEnum = TypeVar("_TIntEnum", bound="_IntEnum")
	_TIntEnum = TypeVar("_TIntEnum", bound=enum.IntEnum)

[YuriiMotov]

Suggested change

	if not issubclass(enum_type, _IntEnum):
	if not issubclass(enum_type, enum.IntEnum):