✨ Add overload for exec method to support insert, update, delete statements

[seriaati]

To address #909

[superboum]

On #1349 you asked for feedbacks on your PR: I tested it and it fixed my typing errors!

Previously I had this mypy output:

src/ddd/infrastructure/manager.py:263: error: No overload variant of "exec" of "Session" matches argument type "Update"  [call-overload]
src/ddd/infrastructure/manager.py:263: note: Possible overload variants:
src/ddd/infrastructure/manager.py:263: note:     def [_TSelectParam: Any] exec(self, statement: Select[_TSelectParam], *, params: Mapping[str, Any] | Sequence[Mapping[str, Any]] | None = ..., execution_options: Mapping[str, Any] = ..., bind_arguments: dict[str, Any] | None = ..., _parent_execute_state: Any | None = ..., _add_event: Any | None = ...) -> TupleResult[_TSelectParam]
src/ddd/infrastructure/manager.py:263: note:     def [_TSelectParam: Any] exec(self, statement: SelectOfScalar[_TSelectParam], *, params: Mapping[str, Any] | Sequence[Mapping[str, Any]] | None = ..., execution_options: Mapping[str, Any] = ..., bind_arguments: dict[str, Any] | None = ..., _parent_execute_state: Any | None = ..., _add_event: Any | None = ...) -> ScalarResult[_TSelectParam]

After applying your patch, the type error is solved.
Thanks a lot, hope your patch will be merged soon so everyone can benefit from this typing fix in sqlmodel 🌟

[pizzashuai]

Hope this gets merged soon! Good job @seriaati

[YuriiMotov]

LGTM!

This fixes the typing issue when we use exec method with insert, update or delete statements. Currently it works, but type checkers raise warnings. This PR fixes this.

@seriaati, thanks for working on this!