Refactor: Split HasValidate implementations for four different extractors into multiple files and export them using feature flags

src/json.rs

@@ -0,0 +1,21 @@
+//! # Implementation of the `HasValidate` trait for the `Json` extractor.
+//!
+
+use crate::{HasValidate, ValidRejection};
+use axum::extract::rejection::JsonRejection;
+use axum::Json;
+use validator::Validate;
+
+impl<T: Validate> HasValidate for Json<T> {
+    type Validate = T;
+    type Rejection = JsonRejection;
+    fn get_validate(&self) -> &T {
+        &self.0
+    }
+}
+
+impl From<JsonRejection> for ValidRejection<JsonRejection> {
+    fn from(value: JsonRejection) -> Self {
+        Self::Inner(value)
+    }
+}