Why do we need a feature here? I think we always want to enable this right?

Backward compatibility. Not a must, I just think it's better to ship with derive by default like it used to be.

We have two features in sea-orm-macros

1. derive - provide all derive macros of SeaORM, e.g. DeriveEntityModel
2. strum - provide the EnumIter derive macros

I split the sea-orm-macros in half because one can opt-out the derive feature in SeaORM by specifying sea-orm = { version = "*", default-features = false }. Where the sea-orm-macros is a optional dependency. But now, the strum reside in it, making it a "compulsory" dependency. Instead, we turn on / off the derive feature as needed.

In contrast, we ALWAYS want the strum feature to be enabled.

Hence,

- sea-orm-macros = { version = "0.11.0", path = "sea-orm-macros", default-features = false, optional = true }
+ sea-orm-macros = { version = "0.11.0", path = "sea-orm-macros", default-features = false, features = ["strum"] }

[features]
- macros = ["sea-orm-macros", "sea-query/derive"]
+ macros = ["sea-orm-macros/derive", "sea-query/derive"]

Umm. This sounds complicated. Well but let it be for now.

Same, I think we can just ship it by default

For this, dependency are conditionally enabled when a feature is being enabled.

This should be fine. If we decided to keep derive and strum as it's now.