Include np.ndarray as possible type for coord values

I originally tried numpy's ArrayLike, replacing Sequence entirely, but then I realized
that ArrayLike also allows non-sequences like integers and floats.

I am not certain if `values="a string"` should be legal. With the type hint sequence, it is.
Might be more accurate, but verbose to use `list | tuple | set | np.ndarray | None`.

pymc/model/core.py

@@ -900,7 +900,7 @@ def shape_from_dims(self, dims):
     def add_coord(
         self,
         name: str,
-        values: Sequence | None = None,
+        values: Sequence | np.ndarray | None = None,
         mutable: bool | None = None,
         *,
         length: int | Variable | None = None,