fix: remove EnumString from empty RewardLevel enum for strum 0.28.0 compatibility

[Copilot]

strum 0.28.0 changed EnumString macro expansion behavior — deriving it on an empty enum now generates unreachable code, causing cargo clippy -- -D warnings to fail.

Change

Removed EnumString from RewardLevel {} in crates/primitives/src/rewards.rs:

// Before
#[derive(Clone, Copy, Debug, Serialize, Deserialize, EnumIter, EnumString, AsRefStr, PartialEq)]
pub enum RewardLevel {}

// After
#[derive(Clone, Copy, Debug, Serialize, Deserialize, EnumIter, AsRefStr, PartialEq)]
pub enum RewardLevel {}

EnumString on an empty enum is a no-op (no variants to parse), so removing it has no behavioral impact.

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.

[semanticdiff-com]

Review changes with  

Changed Files

File	Status
crates/primitives/src/rewards.rs	9% smaller