✨: add HasArrayNeg protocol to support unary minus operator

Author: nstarman

src/array_api_typing/_array.py

@@ -45,9 +45,25 @@ def __pos__(self) -> Self:
         ...
 
 
+class HasArrayNeg(Protocol):
+    """Protocol for array classes that support the unary minus operator."""
+
+    def __neg__(self) -> Self:
+        """Evaluates -self_i for each element of an array instance.
+
+        Returns:
+            an array containing the evaluated result for each element in self.
+            The returned array must have a data type determined by Type
+            Promotion Rules.
+
+        """
+        ...
+
+
 class Array(
     HasArrayNamespace[NS_co],
     HasArrayPos,
+    HasArrayNeg,
     Protocol,
 ):
     """Array API specification for array object attributes and methods."""